Samacheer Kalvi 12th Commerce Solutions Chapter 24 Types of Entrepreneurs

Enhance your subject knowledge with Tamilnadu State Board Solutions for 24th Commerce Chapter 24 Types of Entrepreneurs Questions and Answers and learn all the underlying concepts easily. Make sure to learn the subject from Tamilnadu State Board Solutions Chapter 24 Types of Entrepreneurs Questions and Answers PDF on a day to day basis and score well in your exams. You can Download Samacheer Kalvi 24th Commerce Book Solutions Questions and Answers are given after enormous research by people having high subject knowledge and for better scoring grade. You can rely on them and prepare any topic of Commerce as per your convenience easily.

Tamilnadu Samacheer Kalvi 12th Commerce Solutions Chapter 24 Types of Entrepreneurs

Students those who are looking for Tamilnadu State Board Solutions Chapter 24 Types of Entrepreneurs Questions and Answers Concepts can find them all in one place from our site Tamilnadu State Board Solutions. Simply click on the links available to prepare the corresponding topics of Samacheer Kalvi 24th Commerce Book Solutions Questions and Answers easily. Clarify all your queries from chapter wise different questions to be familiar with the kind of questions appearing in the exam. Thus, you can increase your score and get higher grade in the final exam.

Samacheer Kalvi 12th Commerce Types of Entrepreneurs Textbook Exercise Questions and Answers

I. Choose the Correct Answer

Question 1.
Choose the type of entrepreneur that isn’t based on function:
(a) Innovative
(b) Classical
(c) Fabian
(d) Drone
Answer:
(c) Fabian

Question 2.
Choose the type of Entrepreneur that is not based on Motivation:
(a) Pure
(b) Corporate
(c) Spontaneous
(d) Induced
Answer:
(c) Spontaneous

Question 3.
Which of the following is the Activity of a Business Entrepreneur?
(a) Production
(b) Marketing
(c) Operation
(d) All of the above
Answer:
(d) All of the above

Question 4.
Find the odd one out in context of Trading Entrepreneur.
(a) Selling
(b) Commission
(c) Buying
(d) Manufacturing
Answer:
(d) Manufacturing

Question 5.
Corporate Entrepreneur is also called as  _________
(a) Intrapreneur
(b) Promoter
(c) Manager
(d) Shareholder
Answer:
(b) Promoter

Question 6.
Poultry, Flowers, Fruits, etc., are called allied products of _________ entrepreneur.
(a) Corporate
(b) Retail
(c) Trading
(d) Agricultural
Answer:
(d) Agricultural

Question 7.
_________ Entrepreneur Supply Services Unlike.
(a) Hoteliers
(b) Banking
(c) Airlines
(d) Livestock
Answer:
(d) Livestock

Question 8.
Motive of a Pure Entrepreneur is _________
(a) Rendering service
(b) Earning profit
(c) Attaining status
(d) Both b and c
Answer:
(d) Both b and c

Question 9.
Which of these is based on Technology?
(a) Modem
(b) Professional
(c) Corporate
(d) Industrial
Answer:
(c) Corporate

Question 10.
Which of the below is not a characteristic of a Fabian Entrepreneur?
(a) Conservative
(b) Risk averse
(c) Sceptical
(d) Adaptive
Answer:
(d) Adaptive

II. Very Short Answer Questions

Question 1.
What is the other name of business entrepreneur?
Answer:
The term entrepreneur means the. person who takes steps for commencing the business. So he is otherwise called as organiser or proprietor.

Question 2.
Mention the other name for corporate entrepreneur.
Answer:
Corporate entrepreneur is called promoter. He/she takes initiative necessary to start an entity under corporate format.

Question 3.
Who are agricultural entrepreneur?
Answer:
Agricultural entrepreneurs are those entrepreneurs who raise farm products and market them.

Question 4.
State the name of the.following ventures:
a. Started by individuals for profit motive
b. Started by Government
c. Started by individuals and Government together
d. Started as a family business
Answer:
a. Private entrepreneur
b. State entrepreneurship
c. Induced entrepreneur
d. Classical entrepreneur

Question 5.
Give some examples of pure entrepreneurs.
Answer:
Dhirubai Ambani, Jamshedji Tata, T.V. Sundaram Iyengar, Seshadriji, Birla, Narayanamurthi, and Azim Premji are few examples of pure entrepreneurship.

III. Short Answer Questions

Question 1.
Who is a private entrepreneur?
Answer:
Ventures started by individual either singly or collectively at their own risk after mobilising – various, resources in order to earn profit are called private entrepreneurship.

Question 2.
What is political environment?
Answer:
To commence business, various factors are needed. Apart from all other factors, political environment is also essential. It means that the concessions, incentives provided by the government drive them to enter into venture. The government also provides support in the form of loans, subsidies and other taxes.

Question 3.
List down few examples of pure entrepreneurship.
Answer:
Pure entrepreneurs are individuals who are propelled to enter into venture by psychological and economic motives. They nurture desire of starting a particular venture and earning high profit there from and thus attaining a social status. They apply their knowledge, skill and insight in making the venture a great’ success in order to earn maximum profit out of the venture. Dhirubai Ambani, Jamshedji Tata, T.V. Sundaram Iyengar, Seshadriji, Birla, Narayanamurthi, and Azim Premji are few examples of pure entrepreneurship.

Question 4.
How does a professional entrepreneur operate?
Answer:
Professional entrepreneur is one who is having a rich expertise in starting a venture but lack interest in continuing the venture as a manager or as a owner. He/she simply sells out the venture started by him to someone else after its successful take-off.

Question 5.
Explain, about the agricultural entrepreneur.
Answer:
Agricultural entrepreneurs are those entrepreneurs who raise farm products and market them. They use the various inputs like labour, fertilizer, insecticide, water technology, etc., to raise the products and market their products either directly or through co-operative entities or through brokers or through tie up with large retailers.

IV. Long Answer Questions

Question 1.
Explain in detail on classification according to the type of business.
Answer:
Classification of Entrepreneur according to the type of business:

(i) Business Entrepreneur: He is called solo entrepreneur. He is the one who finds out an idea for a new product or service and establish a business enterprise.

(ii) Trading Entrepreneur: Trading entrepreneurs are those who restrict themselves to buying and selling finished goods.

(iii) Industrial Entrepreneur: These are entrepreneurs who manufacture products to cater to

(iv) Corporate Entrepreneur: He is called as promoter. He takes initiative necessary to start an entity under corporate format.

(v) Agricultural Entrepreneur: These entrepreneurs are those who raise farm products and market them.

Question 2.
Discuss the nature of functional entrepreneurs.
Answer:
Nature of functional entrepreneurs:

(i) Innovative Entrepreneur: He is a person who introduces new project. They observe the environment regarding information to the new venture.

(ii) Imitative Entrepreneur: He refers to the person who simply imitates existing knowledge or technology already in advance countries. Redesigning of products suited to the local conditions.

(iii) Fabian Entrepreneur: These are said to be conservatives and sceptical about any changes in their organisation. They are of risk-averse.

(iv) Drone Entrepreneur: Drone entrepreneurs are those who are totally opposed to changes in the environment. They used to operate in the-niche market.

Question 3.
Distinguish between the rural and urban entrepreneur.
Answer:

S. No.Rural EntrepreneurUrban Entrepreneur
1.It refers to the person who starts business in rural areas.It refers to the person who commences business in urban areas.
2.These entrepreneurs start doing business in the villages and small towns.They will do their business in state capital, towns, district headquarters, municipalities, etc.
3.They may be agricultural and trading entrepreneurs.They may be industrial or corporate entrepreneur.
4.The availability of material and labour is easy. So the cost of operation tends to be low.The availability of material and labour may be difficult. So the cost of operation may be high.

Samacheer Kalvi 12th Commerce Types of Entrepreneurs Additional Questions and Answers

I. A. Choose the Correct Answer

Question 1.
The entrepreneurs classified on the basis of type of business are __________
(i) Industrial entrepreneur
(ii) Technical entrepreneur
(iii) Professional entrepreneur
(iv) Business entrepreneur
(a) (i) and (iii)
(b) (i) and (iv)
(c) (ii) and (iii)
(d) (ii) and (iv)
Answer:
(b) (i) and (iv)

B. Fill in the blanks

Question 1.
Entrepreneur who commences his entrepreneurial activity in urban areas is called as __________
Answer:
urban entrepreneur

II. Very Short Answer Questions

Question 1.
Who is a service entrepreneur?
Answer:
The entrepreneurs enter into the business of giving service products to end consumers. Example: Banking, Insurance and Transport services.

Question 2.
Write a short note on retail entrepreneurs.
Answer
Retail entrepreneurs are those who enter into venture of distributing the end product to final consumer. They used to buy the goods from numerous wholesalers.

III. Short Answer Questions

Question 1.
Who are industrial entrepreneurs?
Answer:
Industrial entrepreneurs are those persons who manufacture products to cater the needs of the consumers. They may be small, medium and large entrepreneurs. Industrial entrepreneurs mobilise the resources of various types’.

Question 2.
Who are technical entrepreneurs?
Answer:
Technical entrepreneurs are those craftsmen like welder, fitter, turner, carpenter and goldsmith, photographer, weaver who start small business. They manufacture products/service of high quality. They simply focus on production rather than on marketing.

We as a team believe the information prevailing regarding the Tamilnadu State Board Solutions for 24th Commerce Chapter 24 Types of Entrepreneurs Questions and Answers has been helpful in clearing your doubts to the fullest. For any other help do leave us your suggestions and we will look into them. Stay in touch to get the latest updates on Tamilnadu State Board Solutions for different subjects in the blink of an eye.

Samacheer Kalvi 12th Commerce Solutions Chapter 23 Elements of Entrepreneurship

Enhance your subject knowledge with Tamilnadu State Board Solutions for 23th Commerce Chapter 23 Elements of Entrepreneurship Questions and Answers and learn all the underlying concepts easily. Make sure to learn the subject from Tamilnadu State Board Solutions Chapter 23 Elements of Entrepreneurship Questions and Answers PDF on a day to day basis and score well in your exams. You can Download Samacheer Kalvi 23th Commerce Book Solutions Questions and Answers are given after enormous research by people having high subject knowledge and for better scoring grade. You can rely on them and prepare any topic of Commerce as per your convenience easily.

Tamilnadu Samacheer Kalvi 12th Commerce Solutions Chapter 23 Elements of Entrepreneurship

Students those who are looking for Tamilnadu State Board Solutions Chapter 23 Elements of Entrepreneurship Questions and Answers Concepts can find them all in one place from our site Tamilnadu State Board Solutions. Simply click on the links available to prepare the corresponding topics of Samacheer Kalvi 23th Commerce Book Solutions Questions and Answers easily. Clarify all your queries from chapter wise different questions to be familiar with the kind of questions appearing in the exam. Thus, you can increase your score and get higher grade in the final exam.

Samacheer Kalvi 12th Commerce Elements of Entrepreneurship Textbook Exercise Questions and Answers

I. Choose the Correct Answer

Question 1.
Which of the below is a factor of production?
(a) Land
(b) Labour
(c) Entrepreneurship
(d) All of the above
Answer:
(d) All of the above

Question 2.
Entrepreneur is not classified as ________
(a) Risk Bearer
(b) Innovator
(c) Employee
(d) Organizer
Answer:
(b) Innovator

Question 3.
What are the characteristics of an entrepreneur?
(a) Spirit of enterprise
(b) Flexibility
(c) Self Confidence
(d) All of the above
Answer:
(d) All of the above

Question 4.
Which of the below is not classified into managerial functions?
(a) Planning
(b) Marketing
(c) Organizing
(d) Controlling
Answer:
(c) Organizing

Question 5.
Which of the below is a commercial function?
(a) Accounting
(b) Coordination
(c) Discovery of idea
(d) Planning
Answer:
(a) Accounting

II. Very Short Answer Questions

Question 1.
Mention any two features of entrepreneurs.
Answer:
Features of Entrepreneurs:

  1. Spirit of Enterprise: Entrepreneur should be bold enough to encounter risk arising from the venture undertaken.
  2. Self Confidence: Entrepreneur should have a self confidence in order to achieve high goals in the business.

Question 2.
List down the managerial functions of entrepreneurs.
Answer:

  1. Planning
  2. Organising
  3. Directing
  4. Controlling
  5. Coordination

Question 3.
List down the promotional functions of entrepreneurs.
Answer:

  1. Discovery of Idea
  2. Determining the business objectives
  3. Detailed Investigation
  4. Choice of form of enterprise
  5. Fullfillment of the formalities
  6. Preparation of Business Plan
  7. Mobilisation of funds
  8. Procurement of Machines and Materials

Question 4.
Define Intrapreneur.
Answer:
Intrapreneur is one who thinks and acts like an entrepreneur for the firm’s development during the course of employment in an organisation.

Question 5.
List the problems faced by the women entrepreneurs.
Answer:
There is a tremendous growth in the women entrepreneurship in India. But there are certain problems met by women entrepreneurs. They are as follows:-

  1. Problem of Finance: The external sources of funds for the women is limited because they do not generally own properties in their own name. They are depending on their own savings and small loans from friends and relatives.
  2. Lack of Education: Illiterate and semi-literate women entrepreneurs face difficulties in respect of accounts, money matters, marketing and day-to-day operations.
  3. Lack of Network Support: The success of business depends on the support of family members, friends and relatives. But it is reported that the women entrepreneurs get very limited support in times of crisis.
  4. Stiff Competition: They have to face acute competition for their goods from organised sector and from their male counterparts.
  5. Lack of Information: The lack of knowledge or limited knowledge about subsidies, concessions and incentives given by Government will affect the business.

III. Short Answer Questions

Question 1.
Define Entrepreneur.
Answer:
The person who establishes business is termed as entrepreneur. The output of an entrepreneurial process ends up in establishing an enterprise.

Question 2.
Distinguish between Entrepreneur and Manager.
Answer:

Basis of differenceEntrepreneurManager
MotiveThe very motive of an entrepreneur is to start a venture by setting of an entity.The very motive of manager is to render service in an entity setup for execution of venture.
StatusEntrepreneur is owner of the entity.Manager is a salaried employee in the entity set up for carrying on the venture.
Risk BearingEntrepreneur bears the eventual risk and uncertainty in operating the enterprise.Manager doesn’t bear any risk in the venture, where the venture is unsuccessful he/she simply quits the enterprise.

Question 3.
List down the commercial functions of Entrepreneur and explain them shortly.
Answer:
Commercial Functions of Entrepreneur:

(i) Production or Manufacturing: Under production function, entrepreneur has to take decision relating to selection of factory site, design and layout, type of products to be manufactured, research and development, product design, etc.

(ii) Marketing: Entrepreneur has to carry out following functions pertaining to marketing aspect namely consumer research, product planning and development, standardisation, packaging, pricing, warehousing, distribution, promotion etc.

(iii) Accounting: Entrepreneur has to arrange to prepare trading and profit and loss account in order to know the profit or loss incurred out of operation of the business and prepare balance sheet to know the financial status of business at a particular day.

(iv) Finance: In the sphere of financial function, an entrepreneur has to take decisions like choosing the right type of financing, framing the best dividend policy, acquiring of funds, efficiently managing fixed and current assets, maximising shareholders wealth and investing of funds efficiently and effectively.

(v) Human Resource Management: Entrepreneur has to estimate the manpower needs of the enterprise and accordingly decide the size of manpower required for various slots of organisational structure.

Question 4.
Explain the promotional functions of entrepreneur.
Promotional Functions of Entrepreneur
Answer:
(i) Discovery of Idea: The first and foremost function of entrepreneur is idea generation. A person may conceive his own ideas or develop the ideas contributed by others. Ideas can be generated through several ways like own experience and exposure of entrepreneur, keen observation of environment, education, training, market survey, environmental scanning and so on.

(ii) Determining the business objectives: Entrepreneur has to develop business objectives in the backdrop of nature of business and type of business activity i.e. nature of business, manufacturing or trading, type of business organisation chosen so that he/she can organise the venture in accordance with the objectives determined by him/her.

(iii) Detailed Investigation: Entrepreneur should investigate commercial feasibility of the product proposed to be produced and conduct market study to ascertain the potential demand for the product.

(iv) Choice of form of enterprise: Entrepreneur has to choose the appropriate form of organisation suited to implement the venture. There are various forms of organisation namely sole proprietor, partnership, company and co-operatives etc. which are in existence.

(v) Fulfilment of the formalities: Having chosen the appropriate type of organisation, entrepreneur has to take necessary steps to establish the form of organisation chosen. As regards sole trader, the formalities are barest minimum. In the case of partnership firm, entrepreneur has to arrange for partnership deed and he has to get the deed registered.

(vi) Preparation of Business Plan: Entrepreneur has to prepare a business plan or project report of the venture that he is proposing to take up.

(vii) Mobilisation of funds: Entrepreneur has to take steps to mobilise capital needed to implement the venture. Entrepreneur has to estimate the fixed capital and working capital required for running the project.

(viii) Procurement of Machines and Materials: Entrepreneur has to locate the various sources of supply of machineries, equipments and materials.

Question 5.
Explain the commercial functions of entrepreneur.
Answer:
(i) Production or Manufacturing: Under production function, entrepreneur has to take decision relating to selection of factory site, design and layout, type of products to be manufactured, research and development, product design, etc. The efficient and effective performance of production function depends on the proper production planning and control to a major extent.

(ii) Marketing: Entrepreneur has to carry out following functions pertaining to marketing aspect namely consumer research, product planning and development, standardisation, packaging, pricing, warehousing, distribution, promotion etc. The term marketing mix denotes the combination of four components namely product, price, promotion and physical distribution in the case of physical products and three more components are included in the case of service products namely people, process and physical evidence.

(iii) Accounting: Entrepreneur has to arrange to prepare trading and profit and loss account in order to know the profit or loss incurred out of operation of the business and prepare balance sheet to know the financial status of business at a particular day. Besides, cash flow and fund flow statements are prepared to ensure the adequacy of funds and cash for meeting various working capital needs of the business.

(iv) Finance: In the sphere of financial function, an entrepreneur has to take decisions like choosing the right type of financing, framing the best dividend policy, acquiring of funds, efficiently managing fixed and current assets, maximising shareholders wealth and investing of funds efficiently and effectively.

(v) Human Resource Management: Entrepreneur has to estimate the manpower needs of the enterprise and accordingly decide the size of manpower required for various slots of organisational structure. After determining the required manpower, the entrepreneur has to organise for recruitment procedure

selecting manpower, induction and training, determining compensation structure and incentives, designing motivation programmes, structuring wellbeing measures for employees, putting in place safety mechanism at workplace, performance evaluation and career advancement and structuring social security programmes.

IV. Long Answer Questions

Question 1.
How do you classify entrepreneurs?
Answer:
Entrepreneurs are now broadly classified into three groups namely risk bearer, organiser and
innovator.

1. Entrepreneur as a risk bearer : Entrepreneurs acts as an agent combining all factors of production to produce a product or service in order to sell at uncertain price in future.

2. Entrepreneur as an organiser : Entrepreneur is one who brings together various factors of production and creates an entity to produce product or service and supervise and coordinates several functions in the process.

3. Entrepreneur as an innovator : According to Joseph A. Schumpeter in the year 1934 used innovation as a criterion to define an individual as entrepreneur. According to him, entrepreneur is one who

    • Introduces a brand new product in the market.
    • Institutes new technology to produce a new product.
    • Discovers new course of supply of raw materials.

Question 2.
What are the characteristics of an entrepreneur?
Answer:
Characteristics of an Entrepreneur:

1. Spirit of Enterprise: Entrepreneur should be bold enough to encounter risk arising from Elements of Entrepreneurship 145 the venture undertaken.

2. Self-confidence: Entrepreneur should have self-confidence in order to achieve high goals in the business.

3. Flexibility: Entrepreneur should not doggedly stick to decisions in a rigid fashion.

4. Innovation: Entrepreneur should contribute something new or something unique to meet the changing requirements of customers namely new product, new method of production or distribution, adding new features to the existing product, uncovering a new territory for business, innovating new raw material, etc.

5. Resource Mobilisation: Entrepreneur should have the capability to mobilise both tangible inputs like manpower, money materials, technology, market, method etc., which are scattered over a wide area and certain intangible inputs like motivation, morale and innovativeness.

Question 3.
Distinguish between an Entrepreneur and an Intrapreneur.
Answer:

Samacheer Kalvi 12th Commerce Solutions Chapter 23 Elements of Entrepreneurship

Question 4.
Discuss the problems faced by Women Entrepreneurs.
Answer:
There is a tremendous growth in the women entrepreneurship in India. But there are certain problems met by women entrepreneurs.
They are as follows:-

  1. Problem of Finance: The external sources of funds for the women is limited because they do not generally own properties in their own name. They are depending on their own savings and loan from friends and relatives.
  2. Lack of Education: Illiterate and semi-literate women entrepreneurs face difficulties in respect of accounts, money matters, marketing and day-to-day operations.
  3. Lack of Network Support: The success of business depends on the support of family members, friends and relatives. But it is reported that the women entrepreneurs get very limited support in times of crisis.
  4. Stiff Competition: They have to face acute competition for their goods from organised sector and from their male counterparts.
  5. Lack of Information: The lack of knowledge or limited knowledge about subsidies, concessions and incentives given by Government will affect the business.

Question 5.
Explain in detail the various functions of an entrepreneur.
Answer:
The functions of an entrepreneur is divided into
(a) Promotional functions,
(b) Managerial functions
(c) Commercial functions.

(a) Promotional functions:
(i) Discovery of Idea: The first and foremost function of entrepreneur is idea generation. A person may conceive his own ideas or develop the ideas contributed by others. Ideas can be generated through several ways like own experience and exposure of entrepreneur, keen observation of environment, education, training, market survey, environmental scanning and so on.

(ii) Detailed Investigation: Entrepreneur should investigate commercial feasibility of the product proposed to be produced and conduct market study to ascertain the potential demand for the product.

(iii) Mobilisation of funds: Entrepreneur has to take steps to mobilise capital needed to implement the venture. Entrepreneur has to estimate the fixed capital and working capital required for running the project.

(b) Managerial functions:
(i) Planning: In this function, the entrepreneur has to lay down the objectives, goals, vision, mission, policies, procedures, programmes, budget, schedules etc., for enabling the venture to proceed towards established destinations.

(ii) Directing: In this function, the entrepreneur has to motivate, lead, guide and communicate with subordinates on an ongoing basis in order to accomplish pre-set goals.

(c) Commercial functions:
(i) Production or Manufacturing: Under production function, entrepreneur has to take decision relating to selection of factory site, design and layout, type of products to be manufactured, research and development.

(ii) Accounting: Entrepreneur has to arrange to prepare trading and profit and loss account in order to know the profit or loss incurred out of operation of the business and prepare balance sheet to know the financial status of business.

We as a team believe the information prevailing regarding the Tamilnadu State Board Solutions for 23th Commerce Chapter 23 Elements of Entrepreneurship Questions and Answers has been helpful in clearing your doubts to the fullest. For any other help do leave us your suggestions and we will look into them. Stay in touch to get the latest updates on Tamilnadu State Board Solutions for different subjects in the blink of an eye.

Samacheer Kalvi 12th Commerce Solutions Chapter 22 The Negotiable Instruments Act 1881

Enhance your subject knowledge with Tamilnadu State Board Solutions for 22th Commerce Chapter 22 The Negotiable Instruments Act 1881 Questions and Answers and learn all the underlying concepts easily. Make sure to learn the subject from Tamilnadu State Board Solutions Chapter 22 The Negotiable Instruments Act 1881 Questions and Answers PDF on a day to day basis and score well in your exams. You can Download Samacheer Kalvi 22th Commerce Book Solutions Questions and Answers are given after enormous research by people having high subject knowledge and for better scoring grade. You can rely on them and prepare any topic of Commerce as per your convenience easily.

Tamilnadu Samacheer Kalvi 12th Commerce Solutions Chapter 22 The Negotiable Instruments Act 1881

Students those who are looking for Tamilnadu State Board Solutions Chapter 22 The Negotiable Instruments Act 1881 Questions and Answers Concepts can find them all in one place from our site Tamilnadu State Board Solutions. Simply click on the links available to prepare the corresponding topics of Samacheer Kalvi 22th Commerce Book Solutions Questions and Answers easily. Clarify all your queries from chapter wise different questions to be familiar with the kind of questions appearing in the exam. Thus, you can increase your score and get higher grade in the final exam.

Samacheer Kalvi 12th Commerce The Negotiable Instruments Act 1881 Textbook Exercise Questions and Answers

I. Choose the Correct Answer

Question 1.
Negotiable Instrument Act was passed in the year ________
(a) 1981
(b) 1881
(c) 1994
(d) 1818
Answer:
(b) 1881

Question 2.
Negotiable Instrument is freely transferable by delivery if it is a ________ instrument.
(a) Order
(b) Bearer
(c) Both a and b
(d) None of the above
Answer:
(b) Bearer

Question 3.
The transferee of a Negotiable Instrument is the one ________
(a) Who transfer the instrument
(b) On whose name it is transferred
(c) Who enchases it
(d) None of the above
Answer:
(b) On whose name it is transferred

Question 4.
Number of parties in a bill of exchange are ________
(a) 2
(b) 6
(c) 3
(d) 4
Answer:
(c) 3

Question 5.
Section 6 of Negotiable Instruments Act 1881 deals with ________
(a) Promissory Note
(b) Bills of exchange
(c) Cheque
(d) None of the above
Answer:
(c) Cheque

Question 6.
________ cannot be a bearer instrument.
(a) Cheque
(b) Promissory Note
(c) Bills of exchange
(d) None of the above
Answer:
(a) Cheque

Question 7.
When crossing restrict further negotiation ________
(a) Not negotiable crossing
(b) General Crossing
(c) A/c payee crossing
(d) Special crossing
Answer:
(a) Not negotiable crossing

Question 8.
Which endorsement relieves the endorser from incurring liability in the event of dishonour?
(a) Restrictive
(b) Facultative
(c) Sans recourse
(d) Conditional
Answer:
(b) Facultative

Question 9.
A cheque will become stale after ________ months of its date.
(a) 3
(b) 4
(c) 5
(d) 1
Answer:
(a) 3

Question 10.
Document of title to the goods exclude ________
(a) Lorry receipt
(b) Railway receipt
(c) Airway bill
(d) Invoice
Answer:
(d) Invoice

II. Very Short Answer Questions

Question 1.
What is meant by Negotiable Instrument?
Answer:
A negotiable instrument is a document which entitles a person to a certain sum of money and which is transferable from one person to another by mere delivery or by endorsement and delivery.

Question 2.
Define Bill of Exchange.
Answer:
According to section 5 of the Negotiable Instruments Act, “a bill of exchange is an instrument in writing containing an unconditional order, signed by the maker, directing a certain person to pay a certain sum of money only to, or to the order of a certain person or to the bearer of the – instrument”.

Question 3.
List three characteristics of a Promissory Note.
Answer:
Characteristics of a Promissory Note:

  1. A promissory note must be in writing.
  2. The promise to pay must be unconditional.
  3. It must be signed by the maker.

Question 4.
What is meant by a cheque?
Answer:
According to section 6 of the Negotiable Instruments Act, 1881 defines a cheque as “a bill of exchange drawn on a specified banker and not expressed to be payable otherwise than on demand”.

Question 5.
Define Endorsement.
Answer:
“When the maker or holder of a negotiable instrument signs the name, otherwise that as such maker for the purpose of negotiation, on the back or face thereof, or on a slip of paper annexed thereto.”

III. Short Answer Questions

Question 1.
Explain the nature of a Negotiable Instrument.
Answer:
A negotiable instrument is transferable from one person to another without any formality, such as affixing stamp, registration, etc. When the instrument is held by holder in due course in the process of negotiation, it is cured of all defects in the instrument with respect to ownership. Though a bill, a promissory note or a cheque represents a debt, the transferee is entitled to sue on the instrument in his own name in case of dishonour, without giving notice to the debtor that he has become its holder.

Question 2.
Distinguish between Negotiability and Assignability.
Answer:

Samacheer Kalvi 12th Commerce Solutions Chapter 22 The Negotiable Instruments Act 1881

Question 3.
What are the characteristics of a bill of exchange?
Answer:
Characteristics of a Bill of Exchange:

  1. A bill of exchange is a document in writing.
  2. The document must contain an order to pay.
  3. The order must be unconditional.
  4. The instrument must be signed by the person who draws it.
  5. The name of the person on whom the bill is drawn must .be specified in the bill itself.

Question 4.
Distinguish between Bill of Exchange and Promissory Note.
Answer:

Samacheer Kalvi 12th Commerce Solutions Chapter 22 The Negotiable Instruments Act 1881

IV. Long Answer Questions

Question 1.
Mention the presumptions of Negotiable Instruments.
Answer:
Presumptions of Negotiable Instrument:

  1. Every negotiable instrument is presumed to have been drawn and accepted for consideration.
  2. Every negotiable instrument bearing, a date is presumed to have been made or drawn on such a date.
  3. It is presumed to have been accepted within a reasonable time after the date and before its maturity.
  4. The transfer of a negotiable instrument is presumed to have been made before maturity.
  5. When a negotiable instrument has been lost, it is presumed to have been duly stamped.
  6. The holder of a negotiable instrument is presumed to be a holder in due course.

Question 2.
Distinguish a cheque and a bill of exchange.
Answer:

Samacheer Kalvi 12th Commerce Solutions Chapter 22 The Negotiable Instruments Act 1881

Question 3.
Discuss in detail the features of a cheque.
Answer:
A cheque is a negotiable instrument drawn on a particular banker.
Features:
(i) Instrument in Writings:
A cheque or a bill or a promissory note must be an instrument in writing. Though the law does not prohibit a cheque being written in pencil, bankers never accept it because of risks involved. Alternation is quite easy but detection is impossible in such cases.

(ii) Unconditional Orders:
The instrument must contain an order to pay money. It is not necessary that the word ‘order’ or its equivalent must be used to make the document a cheque. It does not cease to be a cheque just because the world ‘please’ is used before the word pay. Further the order must be unconditional.

(iii) Drawn on a Specified Banker Only:
The cheque is always drawn on a specified banker. A cheque vitally differs from a bill in this respect as latter can be drawn on any person including a banker. The customer of a banker can draw the cheque only on the particular branch of the bank where he has an account.

(v) A Certain Sum of Money Only:
The order must be for payment of only money. If the banker is asked to deliver securities, the document cannot be called a cheque. Further, the sum of money must be certain.

(v) Payee to be Certain:
The cheque must be made payable to a certain person or to the order of a certain person or to the bearer of the instrument. The word, person includes corporate bodies, local authorities, associations, holders of office of an institution etc.

(vi) Signed by the Drawer:
The cheque is to be signed by the drawer. Further, it should tally with specimen signature furnished to the bank at the time of opening the account.

Question 4.
What are the requisites for a valid endorsement?
Answer:
If an endorsement is to be valid, it must possess the following requisites:

  1. Endorsement is to be made on the face of the instrument or on its back.
  2. When there is no space for making further endorsements a piece of paper can be attached
  3. Endorsement for only a part of the amount of the instrument is invalid.
  4. Endorsement is complete only when delivery of the instrument is made.
  5. Signing in block letters does not constitute regular endorsement.
  6. If the payee is an illiterate person, he can endorse it by affixing his thumb impression on the instrument.

Question 5.
Explain the different kinds of endorsements. .
Answer:
When the person signs on the back of the instrument to transfer his interest, it is known as endorsement. The endorsement are of various types:
(i) Blank or general endorsement:
When the endorser puts his mere signature on the back of an instrument without mentioning the name of the person to whom the endorsement is made, it is called Blank Endorsement

(ii) Endorsement in full or special endorsement:
If the endorser, in addition to his signature, mentions the name of the person to whom it is endorsed, is known as endorsement in full or special endorsement.

(iii) Conditional endorsement:
When the endorser of a negotiable instrument makes his liability dependent upon the happening of an event which may or may not happen, it is called conditional endorsement,

(iv) Restrictive endorsement:
When an endorsement restricts or prohibits further negotiability of the instrument, it is called Restrictive Endorsement.

(v) Partial Endorsement:
Where the endorsement seeks to transfer only a part of the amount payable under the instrument, the endorsement is called Partial Endorsement.

Samacheer Kalvi 12th Commerce The Negotiable Instruments Act 1881 Additional Questions and Answers

I. Choose the Correct Answer

Question 1.
A bill of exchange drawn on a specified banker is
(a) promissory note
(b) cheque
(c) hundi
(d) share
Answer:
(b) cheque

Question 2.
Grace days allowed to a Bill of exchange for calculation of due date is
(a) 4
(b) 10
(c) 3
(d) 5
Answer:
(c) 3

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Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life

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Tamilnadu Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life

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Samacheer Kalvi 12th Chemistry Chapter 15 Chemistry in Everyday Life Textual Evaluation Solved

Samacheer Kalvi 12th Chemistry Chemistry in Everyday Life Multiple Choice Questions

Question 1.
Which of the following is an nalgesic?
(a) Streptornycin
(b) Chloromycetin
(c) Asprin
(d) Penicillin
Answer:
(c)Asprin

Question 2.
Dettol is the mixture of ……………
(a) Chioroxylenol and bithionol
(b) Chioroxylenol and a – terpineol
(c) phenol and iodine
(d) terpineol and bithionol
Answer:
(b) Chioroxylenol and a – terpineol

Question 3.
Antiseptics and disinfectants either kill or prevent growth of microorganisms. Identify which of the following statement is not true.
(a) dilute solutions of boric acid and hydrogen peroxide are strong antiseptics
(b) Disinfectants harm the living tissues
(c) A 0.2% solution of phenol is an antiseptic while 1% solution acts as a disinfectant
(d) Chlorine and iodine are used as strong disinfectants
Answer:
(a) dilute solutions of boric acid and hydrogen peroxide are strong antiseptics

Question 4.
Saccharin, an artificial sweetener is manufactured from ……………..
(a) cellulose
(b) toluene
(c) cyclohexene
(d) starch
Answer:
(b) toluene

Question 5.
Drugs that bind to the receptor site and inhibit its natural function are called …………….
(a) antagonists
(b) agonists
(c) enzymes
(d) molecular targets
Answer:
(a) antagonists

Question 6.
Aspirin is a/an ……………..
(a) acetylsalicylic acid
(b) benzoyl salicylic acid
(c) chlorobenzoic acid
(d) anthranilic acid
Answer:
(a) acetylsalicylic acid

Question 7.
Which one of the following structures represents nylon 6,6 polymer?
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-1
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-2

Question 8.
Natural rubber has ………..
(a) alternate cis – and trans – configuration
(b) random cis – and trans-configuration
(c) all cis – configuration
(d) all trans – configuration
Answer:
(c) all cis – conflguration

Question 9.
Nylon is an example of …………..
(a) polyamide
(b) polythene
(c) polyester
(d) poly saccharide
Answer:
(a) polyamide

Question 10.
Terylene is an example of …………..
(a) polyamide
(b) polythene
(c) polyester
(d) poly saccharide
Answer:
(c) polyester

Question 11.
Which is the monomer of neoprene in the following?
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-3
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-4

Question 12.
Which one of the following is a bio-degradable polymer?
(a) HDPE
(b) PVC
(c) Nylon 6
(d) PHBV
Answer:
(d) PHBV

Question 13.
Non stick cook wares generally have a coating of a polymer, whose monomer is ………….
(a) ethane
(b) prop – 2 – enenitrile
(c) chioroethene
(d) 1, 1, 2, 2 – tetrafluoroethane
Answer:
(d) 1, 1, 2, 2 – tetrafluoroethane

Question 14.
Assertion: 2 – methyl – I ,3 – butadiene is the monomer of natural rubber
Reason: Natural rubber is formed through aniònic addition polymerisation.
(a) If both assertion and reason are true and reason is the correct explanation of assertion
(b) if both assertion and reason are true but reason is not the correct explanation of assertion
(c) assertion is true but reason is false
(d) both assertion and reason are false
Answer:
(c) assertion is true but reason is false

Question 15.
An example of antifertility drug is ………….
(a) novesirol
(b) seldane
(c) salvarsan
(d) Chioramphenicol
Answer:
(a) novestrol

Question 16.
The drug used to induce sleep is …………..
(a) paracetamol
(b) bithional
(c) chioroquine
(d) equanil
Answer:
(d) equanil

Question 17.
Which of the following is a co – polymer?
(a) Orlon
(b) PVC
(c) Teflon
(d) PHBV
Answer:
(d) PHBV

Question 18.
The polymer used in making blankets (artificial wool) is ……………
(a) polystyrene
(b) PAN
(c) polyester
(d) polythene
Answer:
(b) PAN

Question 19.
Regarding cross-linked or network polymers, which of the following statement is incorrect?
(a) Examples are Bakelite and melamine
(b) They are formed from bi and tri-functional monomers
(c) They contain covalent bonds between various linear polymer chains
(d) They contain strong covalent bonds in their polymer chain
Answer:
(d) They contain strong covalent bonds in their polymer chain

Question 20.
A mixture of chioroxylenol and terpinecol acts as ……………
(a) antiseptic
(b) antipyretic
(c) antibiotic
(d) analgesic
Answer:
(a) antiseptic

II. Answer the following questions

Question 1.
Which chemical is responsible for the antiseptic properties of dettol?
Answer:
1. Chloroxylenol and

2. Terpineol are the chemicals responsible for the antiseptic properties of dettol. But among these two, chloroxylenol plays more important role. Chioroxylenol is an antiseptic and disinfectant which is used for skin disinfection and cleaning surgical instruments.

Question 2.
What are antibiotics?
Answer:
Antibiotics is a chemical substance produced by one microorganism, that selectively inhibits the growth of another micro organism. Example : penicillins and cephalosporins.

Question 3.
Name one substance which can act as both analgesic and antipyretic.
Answer:
Aspirin (acetylsalicylic acid) is a chemical substance which lowers body temperature (to normal) and also reduces body pain. Therefore it acts as both antipyretic and analgesic.

Question 4.
Write a note on synthetic detergents.
Answer:
1. Synthetic detergents are formulated products containing either sodium salts of alkyl hydrogen suiphates or sodium salts of long chain alkyL benzene suiphonic acids.

2. Synthetic detergents are three types. They are

  • anionic detergents – sodium lauryl sulphate.
  • Cationic detergents – n – hexadecyltrimethyl ammonium chloride.
  • Non-ionic detergents – Pentaerythrityl stearate.

3. Synthetic detergents can be used even in hard water, while soaps cannot be used in hard water.

4. The cleansing action of detergents are similar to the cleansing action of soaps.

5. When detergents are dissolved in water its hydrocarbon part attaches itself to grease and oil particles. Whereas its ionic part remains attached to water. Therefore when dirty clothes are agitated in solution of detergents then dirty particles sticks to the hydrocarbon part of detergents and at the same time the water loving ionic part pulls away this dirt from clothes.

Question 5.
How do antiseptics differ from disinfectants?
Answer:
An tisep tics

  1. Antiseptics are chemical substance which prevent the growth of micro organizers and may even kill them but are not harmful to living tissues.
  2. They are generally applied to living tissues such as wounds, cuts bulks and diseased surfaces.
  3. All the antiseptics are disinfectants.
  4. They are not ingested or swallowed.
  5. e.g., Povidone – iodine, Benzalkonium – Chloride

Disinfectants

  1. Disinfectants are chemical substances which kill microorganism or stop their growth but are harmful to human tissues.
  2. Disinfectants are applied to inanimated objects such as floors, drainage system, instruments etc.
  3. All the disinfectants are not antiseptics.
  4. They can be injected or swallowed.
  5. e.g. Alcohol, chlorine compunds.

Question 6.
What are food preservatives?
Answer:
Food preservatives are chemical substances are capable of inhibiting, retarding or arresting the process of fermentation, acidification or other decomposition of food by growth of micro organisms.
Examples:

  1. Acetic acid is used mainly as a preservative for preparation of pickles.
  2. Sodium meta suiphite is used as preservative for fresh vegetables and fruits.
  3. Sodium benzoate is used as preservative for juices.

Question 7.
Why do soaps not work ¡n hard water?
Answer:
Soaps are sodium or potassium salts of long – chain falty acids. Hard water contains calcium and magnesium ions. When soaps are dissolved in hard water, these ions displace sodium or potassium from insoluble calcium or magnesium salts of fatty acids. These insoluble salts separate as scum.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-5
This is the reason why soaps do not work in hard water.

Question 8.
What are drugs? How are they classified?
Answer:
A drug is a substance that is used to modify or explore physiological systems or pathological states for the benefits of the recipient. it is used for the purpose of diagnosis, prevention cure or relief of a disease.

Classification of drugs:
Drugs care classified based on their proportions such as chemical structure, pharmacological effect, target system, site of action etc.

1. Classification based on the chemical structure:
In this classification, drugs with a common chemical skelton are classified into a single group. For example, ampicillin, amoxicillin, methiceillin etc. all have similar structure and are classified into a single group called penicillin.

Similarly we have other group of drugs such as opiates, steroids, catecholamines etc. Compounds having similar chemical structure are expected to have similar chemical properties. However, their biological actions are not always similar.

2. Classification based on the pharmacological effect:

  • In this classification, the drugs are grouped based on their biological effect that they produce on the recipient.
  • For example, the medicines that have the ability to kill the pathogenic bacteria are grouped as antibiotics.
  • This kind of grouping will provide the full range of drugs that can be used for a particular disease.

3. Classification based on the target system:

  • In this classification, the drugs are grouped based on the biological system (or) process that they target in the recipient.
  • This classification is more specific than the pharmacological classification.
  • For example, the antibiotics streptomycin and erythromycin inhibit the protein synthesis (target) in bacteria and are classified in a same group. However their mode of action is different.
  • Streptomycin inhibits the initiation of protein synthesis, while erythromycin prevents the incorporation of new aminoacids to the protein.

4. Classification based on the site of action:

  1. The drug molecule interacts with biomolecules such as enzymes, receptors etc, which are referred as drug targets.
  2. We can classify the drug based on the drug target with which it binds.
  3. This classification is highly specific compared to the others. These compounds often have a common mechanism of action, as the target is the same.

Question 9.
How the tranquilizers work in body?
Answer:

  1. They are neurologically active drugs.
  2. Tranquilizer acts on the central nervous system by blocking the neurotransitter dopamine in the brain.
  3. This drug is used for treatment of stress anxiety, depression, sleep disorders and severe mental diseases like schizophrenia.

 

Question 10.
Write the structural formula of aspirin.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-6

Question 11.
Explain the mechanism of cleansing action of soaps and detergents.
Answer:
Mechanism of cleansing action of soaps and detergents:
1. The cleansing action of both soaps and detergents from their ability to lower the surface tension of water, to emulsify oil or grease and to hold them in a suspension in water.

2. This ability is due to the structure of soaps and detergents.

3. In water a sodium soap dissolves to form soap anions and sodium cations. For example, the following chemical equation shows the ionisation of sodium palmitate.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-7

4. A soap anion consists of a long hydrocarbon chain with a carboxylate group on one end. The hydrocarbon chain, which is hydrophobic, is soluble in oils or grease. The ionic part is the carboxylate group which is hydrophilic, is soluble in water.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-8

5. In water, detergent dissolves to form detergent anions and sodium cations. For example the following chemical equations show the ionisation of sodium alkyl sulphate and sodium alkyl benzene sulphate.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-9

6. The following explains the cleansing action of a soap or detergent on a piece of cloth with a greasy stain.

  1. A soap or detergent anion consists of a hydrophobic part and a hydrophilic part.
  2. Soap or detergent reduces the surface tension of water. Therefore the surface of the cloth is wetted thoroughly.
  3. The hydrophobic parts of the soap or detergents anions are soluble in grease.
  4. The hydrophilic parts of the anions are soluble in water.
  5. Scrubbing or mechanical agitation helps to pull the grease away from the cloth and the grease is broken into smaller droplets.
  6. Repulsion between the droplets causes the droplets to be suspended in water, fonning an emulsion.
  7. Thus the droplets do not coagulate or,redeposit on the cloth. Rinsing washes away the droplets.

Question 12.
Which sweetening agent are used to prepare sweets for a diabetic patient?
Answer:
Artificial sweetening agents such as,

  1. saccharin
  2. Alitame
  3. Aspartame

can be used in preparing sweets for diabetic patients.

Question 13.
What are narcotic and non – narcotic drugs. Give examples.
Answer:
1. Narcotic drug is an addictive drug that reduces pain, induces sleep and may alter mood or behaviour. Example: Morphine and codeine.

2. Non – narcotic drug are chemical substance (medications) used to control pain and inflammation. They are available at drugstores without a prescription or by prescription when given at higher doses. Example: Acetaminophen and paracetamol.

Question 14.
What are anti fertility drugs? Give examples.
Answer:
Artificially drugs are chemical substances which suppress the action of hormones that promote pregnancy. These drugs actually reduce the chances of pregnancy and act as a protection. Antifertility drugs are made up of derivatives of synthetic progesterone or a combination of derivatives of oestrogen and progesterone. Example : Ethynylestradiol, menstranol and norcthynodrel etc.

Question 15.
Write a note on co – polymer.
Answer:

  1. A polymer containing two or more different kinds of monomer units is called a co-polymer.
  2. Co – polymers have properties quite different from the homopolymers.
  3. The structural units of co-polymers are derived from the different monomers may be present in regular, alternation or in random order or strings of several units of one kind may alternate with strings of another.
  4. For example, Buna – S, Buna – N, Nylon – 6,6 etc. Buna – S contains styrene and butadiene monomer units.

Question 16.
What are bio degradable polymers? Give examples.
Answer:

  1. The materials that are readily decomposed by micro organisms in the environment are called biodegradable.
  2. Natural polymers degrade on their own after certain period of time but the synthetic polymers do not.
  3. The biopolymers which disintergrates by themselves in biological systems during a
  4. certain period of time by enzymatic hydrolysis and to some extent by oxidation are called biodegradable polymers.

Examples:

  1. Polyhydroxy butyrate (PHB)
  2. Polyhydroxy butyrate – co – hydroxyl valerate (PHBV)
  3. Polylactic acid (PLA)

Question 17.
How is terylene prepared?
Answer:
The monomers are ethylene glycol and terephthalic acid or dimethýlterephthalate. When these monomers are mixed and heated at 500K in the presence of zinc acetate and antimonytrioxide catalyst, terylene (or dacron) is formed.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-10

Question 18.
Write a note on vulcanization of rubber.
Answer:

  1. Natural rubber is very soft and brisky. it has high water absorption capacity and low tensile strength. Its properties can be improved by a process called vulcanization.
  2. Natural rubber is mixed with 3 – 5% sulphur and heated at 100 – 150°C causes cross linking of the cis – 1, 4 polyisoprene chains through disuiphide ( – S – S – ) bonds.
  3. The physical properties of rubber can be altered by controlling the amount of sulphur that is used for vulcanization. When 3 to 10% sulphur is used the resultant rubber is somewhat harder but flexible.
  4. Following properties of rubber CH3

Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-11

Question 19.
Classify the following as linear, branched or cross linked polymers …………………..

  1. Bakelite
  2. Nylon
  3. polvthene

Answer:

  1. Bakelite – cross linked polymer
  2. Nylon – Linear polymer
  3. Polythene – Linear polymer

Question 20.
Differentiate thermoplastic and thermosetting.
Answer:
Difference between thermoplastic and thermosetting:
Thermoplastic

  1. They soften on heating and harden on cooling, and they can be remoulded.
  2. They consists of linear long çhain polymers and low molecular weights polymers.
  3. All the polymer chains are held together by weak Vanderwaals forces.
  4. They are weak, soft and less brittle.
  5. They are formed by additon polymerisation
  6. They are soluble in organic solvents.
  7. Example: PVC, polythene, polystrene etc.

Thermosetting

  1. They do not soften on heating and they cannot be remoulded.
  2. The consist of three dimensional network structure and high molecular weight polymers.
  3. All the polymer chains are linked by strong covalent.
  4. They are strong, hard and more brittle.
  5. They are formed by condensation polymerisation.
  6. They are insoluble in organic solvents.
  7. Example: Bakelite, melamine etc.

Samacheer Kalvi 12th Chemistry Chemistry in Everyday Life Additional Questions

Samacheer Kalvi 12th Chemistry Chemistry in Everyday Life 1 mark Questions and Answers

I. Choose the best answer.

Question 1.
The substance that is used to modify physiological system for the benefit of the recipient is called …………….
(a) a drug
(b) a dye
(c) a food preservative
(d) soap
Answer:
(a) a drug

Question 2.
Which one interacts with macromolecular targets such as proteins to produce a therapeutic and useful biological response?
(a) Detergent
(b) cleansing agent
(c) medicine
(d) food preservative
Answer:
(c) medicine

Question 3.
The ratio between the maximum tolerated dose of a drug and a minimum curative dose is called …………..
(a) iso electric point
(b) therapeutic index
(c) critical point
(d) iso thermal point
Answer:
(b) therapeutic index

Question 4.
Which one of the following does not belong to penicillin group?
(a) Ampicillin
(b) Amoxicillin
(c) catecholamine
(d) mithicillin
Answer:
(c) catecholamine

Question 5.
Which of the following does belongs to penicillin group drugs?
(a) Mithicillin
(b) opiates
(c) steroids
(d) catecholamine
Answer:
(a) Mithicillin

Question 6.
Which one of the following is an antibiotic?
(a) erythromycin
(b) atenolol
(c) amlodipine
(d) propranolol
Answer:
(a) erythromycin

Question 7.
Which one of the following is not an antibiotic?
(a) amoxicillin
(b) cefixime
(c) amlodipine
(d) ampiciflin
Answer:
(c) amlodipine

Question 8.
Which one of the following is an example tbr antihypertensive drug?
(a) atenolol
(b) amoxicillin
(c) cefixime
(d) tetracycline
Answer:
(a) atenolol

Question 9.
Which of the following does not belongs to antihypertensive drug?
(a) atenolol
(b) amlodipine
(c) propranolol
(d) erythromycin
Answer:
(d) erythromycin

Question 10.
Which one of the following inhibits the initiation of protein synthesis?
(a) streptomycin
(b) erythromycin
(c) atenolol
(d) amlodipine
Answer:
(a) streptomycin

Question 11.
Which one of the following prevents the incorporation of new amino acids to the protein?
(a) atenolol
(b) streptomycin
(c) erythromycin
(d) tetracycline
Answer:
(c) erythromycin

Question 12.
Which one of the following inhibits the bacterial growth?
(a) p – amino benzoic acid
(b) sulphanilamide
(c) folic cid
(d) sodium benzoate
Answer:
(b) sulphanilamide

Question 13.
Which of the following is needed by many bacteria to produce folic acid?
(a) PABA
(b) DHPS
(c) TNB
(d) GTN
Answer:
(a) PABA

Question 14.
Which of the following is called PABA?
Answer:
(a) p – nitro benzanilic acid
(b) p – amino butyric acid
(c) p – amino benzene suiphonic acid
(d) p – amido benzene suiphonyl chloride
Answer:
(c) p – amino benzene suiphonic acid

Question 15.
Which one of the following binds to the receptor site should inhibit its natural function?
(a) antacids
(b) antioxidant
(c) antibiotics
(d) antagonists
Answer:
(d) antagonists

Question 16.
Which of the following is used in the reduced sleepiness?
(a) caffeine
(b) morphine
(c) suiphanilide
(d) p – aminobenzene sulphonic acid
Answer:
(a) caffeine

Question 17.
Which one of the following is used as painkiller?
(a) lodoform
(b) chloropicrin
(c) morphine
(d) coffeine
Answer:
(c) morphine

Question 18.
Which of the following is not an example of antacid?
(a) Histamine
(b) cimetidine
(c) ranitidine
(d) erythromycin
Answer:
(d) erythromycin

Question 19.
Which one of the following is used as an antacid?
(a) magnesium hydroxide
(b) aluminium hydroxide
(c) ranitidine
(d) all the above
Answer:
(d) all the above

Question 20.
Which one of the following is used to treat stress, anxiety, depression, sleep disorder and schizopherenia?
(a) Tranquilizer
(b) antibiotic
(c) analgesic
(d) opioids
Answer:
(a) Tranquilizer

Question 21.
Which one of the following is an example for tranquilizer?
(a) cimetidine
(b) diazepam
(c) histamine
(d) PABA
Answer:
(b) diazepam

Question 22.
Identify the medine that is used to treat stress, anxiety. depression and schizophrenia.
(a) valium
(b) cimetidinc
(c) chiorofom
(d) adenosine
Answer:
(a) valium

Question 23.
Which one of the following is used to reduce fever and prevent platelet coagulation?
(a) antibiotic
(b) antiseptic
(c) antioxidant
(d) antipyretic
Answer:
(d) antipyretic

Question 24.
Which one of the following is an anti inflamatory drug?
(a) morphine
(b) coheinc
(c) aspirin
(d) histidine
Answer:
(c) aspirin

Question 25.
Which one of the following is used to cure headache, muscle strain, arthritis?
(a) acetaminophen
(b) ibuprofen
(c) aspirin
(d) all the above
Answer:
(d) all the above

Question 26.
Which one of the foLlowing is used in the prevention of heart attacks?
(a) aspirin
(b) ibuprofen
(c) paracetamol
(d) morphine
Answer:
(a) aspirin

Question 27.
Which one of the following is an example of an àntipyretic?
(a) acetyl salicylic acid
(b) methyl salicylate
(c) paraldehyde
(d) diethyl ether
Answer:
(a) acetyl salicylic acid

Question 28.
Which one of the following is a non steroidal anti inflammatory drug?
(a) aspirin
(b) morphine
(c) haloperidol
(d) ibuprofen
Answer:
(d) ibuprofen

Question 29.
Which of the following is a major tranquilizer?
(a) diazepam
(b) valium
(c) clozapine
(d) alprazolm
Answer:
(c) clozapine

Question 30.
Which of the following is a minor tranquilizer?
(a) haloperidol
(b) clozapine
(c) morphine
(d) valium
Answer:
(d) valium

Question 31.
Consider the following statements
(i) Tranquilizers act on the central nervous system by blocking the neurotransmitter dopamine in the brain.
(ii) Histamines stimulate the secretion of HCI by activating the receptor in the stomach wall.
(iii) The antibiotic cimetidine inhibits the bacterial growth.
Which of the above statement is/are not correct?
(a) (i) only
(b) (¡) & (ii)
(c) (iii) only
(d) (ii) only
Answer:
(c) (iii) only

Question 32.
Consider the following statements
(i) Acetaminophen reduces fever by causing the hypothalamus to override a prostaglandin
(ii) opioids relieve pain and produce sleep and are addictive
(iii) Aspirin finds useful in the pain of terminal cancer.
Which of the above statement is/arc not correct?
(a) (i) only
(b) (ii) only
(c) (ii) & (iii)
(d) (iii) only
Answer:
(d) (iii) only

Question 33.
Which of the following are addictive and poisonous drug?
(a) ibuprofen
(b) aspirin
(c) morphine
(d) paracetamol
Answer:
(c) morphine

Question 34.
Which of the following are used for post operative pain and pain of terminal cancer?
(a) morphine, codeine
(b) ibuprofen, aspirin
(c) methyl salicylate, salicylic acid
(d) histidine, ranitidine
Answer:
(a) morphine, codeine

Question 35.
Which one of the following is an local anaesthetic?
(a) lidocaine
(b) Propofol
(c) iso flurane
(d) ibuprofen
Answer:
(a) lidocaine

Question 36.
Which one of the following is an example of general anaesthetic?
(a) propofol
(b) isoflurane
(c) ranitidine
(d) omeprazole
Answer:
(b) isoflurane

Question 37.
Identify the intraveneous general anaesthetics?
(a) milk of magnesia
(b) lidocaine
(c) omeprazole
(d) iso fharane
Answer:
(d) iso fharane

Question 38.
Which one of the following is an inhalational general anaesthetic?
(a) procain
(b) iso fiurane
(c) lidocaine
(d) rabeprazole
Answer:
(b) iso fiurane

Question 39.
Which one of the following is an antacid?
(a) omeprazole
(b) rabeprazole
(c) milk of magnesia
(d) all the above
Answer:
(d) all the above

Question 40.
Consider the following statements.
(i) Propofol cause a controlled and reversible loss of consciousness by affecting central nervous system.
(ii) Ibuprofen is used for major surgical procedures.
(iii) Lidocaine is used to relieve burning sensation in the chest / throat area.
Which of the above statement is/are not correct?
(a) (i) only
(b) (i) & (ii)
(c) (ii) & (iii)
(d) (i) & (iii)
Answer:
(c) (ii) & (iii)

Question 41.
Which one of the following is not an antacid?
(a) propofol
(b) ranitidine
(c) omeprazole
(d) rabeprazole
Answer:
(a) propofol

Question 42.
Which one of the following is used to provide relief from the allergic effects?
(a) cetrizine
(b) ampicillin
(c) erythromycin
(d) milk of magnesia
Answer:
(a) cetrizine

Question 43.
Which one of the following inhibits bacterial cell wall biosynthesis?
(a) eryLhromycin
(b) azithromycin
(c) penicillin
(d) cetrizine
Answer:
(c) penicillin

Question 44.
Which of the following is used to treat respiratory tract infections, genital, gastrointestinal tract and skin infections?
(a) ampicillin
(b) penicillin
(c) terfenadine
(d) azithromycin
Answer:
(d) azithromycin

Question 45.
Which one of the following is used to treat urinary tract infection and respiratory infections?
(a) doxycycline
(b) karamycin
(c) ciprolloxacin
(d) ibuprofen
Answer:
(c) ciprolloxacin

Question 46.
Which of the following is used in the treatment of cholera, acne vulgaris?
(a) fluoro quinolone
(b) aminoglycosides
(c) tetracycline
(d) macrolides
Answer:
(c) tetracycline

Question 47.
Which one of the following is used to treat infections caused by gram negative bacteria?
(a) kanamycin
(b) gentamycin
(c) neomycin
(d) all the above
Answer:
(d) all the above

Question 48.
Which one of the following inhibits bacterial enzyme DNA gyrase?
(a) doxy cycline
(b) kanamycin
(c) ciprofloxacin
(d) aspirin
Answer:
(c) ciprofloxacin

Question 49.
Which one of the following is an antiseptic?
(a) Hydrogen peroxide
(b) alcohol
(c) menstranol
(d) chlorine compounds
Answer:
(a) Hydrogen peroxide

Question 50.
Which one of the following is used to reduce the risk of infection during surgery?
(a) povidone – iodine
(b) ethynyles tradiol
(c) norethindrone
(d) acetyl salicylic acid
Answer:
(a) povidone – iodine

Question 51.
Consider the following statements
(i) Oestrogen, menstranol are synthetic hormones that suppresses ovulation / fertilisation,
(ii) Norethindrone used in birth control pills.
(iii) Chlorine compounds are used to reduce the risk of infection during surgery.
Which of the above statement is/are not correct?
(a) (i) only
(b) (ii) & (iii)
(c) (iii) only
(d) (i) & (iii)
Answer:
(c) (iii) only

Question 52.
Which one of the following is used as a preservative for the preparation of pickles and preservation of vegetables?
(a) sodium acetate
(b) acetic acid
(c) sodium carbonate
(d) salicylic acid
Answer:
(b) acetic acid

Question 53.
Which one is used as preservatives for fresh vegetables and fruits?
(a) Palmitic acid
(b) Palm oil
(c) sodium meta suiphite
(d) sulphur dioxide
Answer:
(c) sodium meta suiphite

Question 54.
Which one of the following is used as an emulsifier?
(a) sodium meta suiphite
(b) sucrose ester of palmiticacid
(c) sodium benzoate
(d) sodium bi carbonate
Answer:
(b) sucrose ester of palmiticacid

Question 55.
Which method is used to preserve food?
(a) pasteurisation & irration
(b) chilling and freezing
(c) drying and dehydration
(d) all the above
Answer:
(d) all the above

Question 56.
Which one of the following act as an antioxidant?
(a) Palmîtic acid
(b) butyl hydroxy toluene
(c) sodium benzoate
(d) Ascorbic acid
Answer:
(b) butyl hydroxy toluene

Question 57.
Consider the following statements.
(i) Addition of vitamins and minerals reduces the mall nutrient.
(ii) Flouring agents reduces the aroma of the food.
(iii) Antioxidants produce the formation of potentially toxic oxidation products of lipids.
Which of the above statement is/are not correct?
(a) (i) only
(b) (ii) only
(c) (ii) & (iii)
(d) (i) & (iii)
Answer:
(c) (ii) & (iii)

Question 58.
Which of the following is not a sugar substituent?
(a) Sorbitol
(b) mannitol
(c) xylitol
(d) cresol
Answer:
(d) cresol

Question 59.
Which of the following is not a sugar substituent?
(a) Butyl hydroxy toluene
(b) Butylated hydroxy anisole
(c) Aspartame
(d) Ascorbic acid
Answer:
(c) Aspartame

Question 60.
Identify the artificial sweeteners.
(a) Saccharin, sucralose
(b) culutaric acid, glycollic acid
(c) BHT, BHA
(d) GTN, TNG
Answer:
(a) Saccharin, sucralose

Question 61.
Glyceryl ester of long chain fatty acids are called …………..
(a) soap
(b) detergent
(c) antiseptic
(d) antibiotic
Answer:
(a) soap

Question 62.
Which one of the following describes the quality of soap?
(a) TFT value
(b) TFM value
(c) PPM value
(d) TFP value
Answer:
(b) TFM value

Question 63.
Sodium salt of long chain allyl benzene sulphomc acids are called ……………….
(a) soap
(b) detergent
(c) disinfectant
(d) antiseptic
Answer:
(b) detergent

Question 64.
Which one of the following is an anionic detergent?
(a) n – hexa decyl tri methyl ammonium chloride
(b) Peifla erythntyl stearate
(c) Sodium lauryl sulphate
(d) 3 – hydroxy – 2, 2 bis (hydroxy methyl) propyl heptonoate
Answer:
(c) Sodium lauryl sulphate

Question 65.
Which of the following is an example of catìonic detergent?
(a) Sodium lauryl sulphate
(b) sodium pahnitate
(c) sodium dodecyl benzene suiphonate
(d) n – hexa decyl timethyl ammonium chloride
Answer:
(d) n – hexa decyl timethyl ammonium chloride

Question 66.
Which one of the following is an example of non-ionic detergent?
(a) sodium lauryl sulphate
(b) n – hexa decyl trimethyl ammonium chloride
(c) Penta erythrityl stearate
(d) N, N, N – trimethyl hexa decan – 1 – aminium chloride
Answer:
(c) Penta erythrityl stearate

Question 67.
Which one of the following is a natural polymer?
(a) cellulose, silk
(b) PVC, Polythene
(c) Buna – N, Buna – S
(d) Bakelite, Nylon 6,6
Answer:
(a) cellulose, silk

Question 68.
Which one of the following is a synthetic rubber?
(a) Neoprene
(b) cellulose
(c) silk
(d) poly isoprene
Answer:
(a) Neoprene

Question 69.
Which one of the following is a semisynthetic polymer?
(a) poly isoprene
(b) viscose rayon
(c) nylon
(d) terylene
Answer:
(b) viscose rayon

Question 70.
Which one of the following is not a cross linked polymer?
(a) poly propylene
(b) bakelite
(c) melamine
(d) urea formaldehyde
Answer:
(a) poly propylene

Question 71.
Identify the thermo setting plastic?
(a) nylon 6, 6
(b) neoprene
(c) melamine
(d) bakelite
Answer:
(c) melamine

Question 72.
Which of the following is a thermoplastic?
(a) bakelite
(b) melamine
(c) urea formaldehyde
(d) polystrene
Answer:
(d) polystrene

Question 73.
Which one of the following is an elastomer?
(a) nylon 6,6
(b) terylene
(c) buna – S
(d) bakelite
Answer:
(c) buna – S

Question 74.
Which one of the following is an example for addition polymer?
(a) polyethylene
(b) PVC
(c) teflon
(d) all the above
Answer:
(d) all the above

Question 75.
Which one of the following is an example of condensation polymer?
(a) poly ethylene
(b) polyester
(c) PVC
(d) teflon
Answer:
(b) polyester

Question 76.
Which one of the following is not an additional polymer?
(a) poly ethylene
(b) PVC
(c) Nylon 66
(d) teflon
Answer:
(c) Nylon 66

Question 77.
Consider the following statements
(i) Nylon-6, 6 are polymerchains form fibres by hydrogen bonding.
(ii) Thermoplastic become hard on heating and soft on cooling and cannot be remoulded.
(iii) Cellulose and silk are synthetic polymers.
Which of the above statement is/are not correct? ,
(a) (i) only
(b) (ii) & (iii)
(c) (iii) only
(d) (i) & (iii)
Answer:
(b) (ii) & (iii)

Question 78.
Which one of the following is used as an free radical initiator in the preparation of polystrene?
(a) hydrogen peroxide
(b) methyl chloride
(c) Benzoyl peroxide
(d) Benzyl peroxide
Answer:
(c) Benzoyl peroxide

Question 79.
Which mechanism is followed in the synthesis of polystrene?
(a) free radical polymerisation
(b) cationic polymensation
(c) Anionic polymerisation
(d) SN1 mechanism

Question 80.
Which one of the polymer is used as insulation for cables, making toys?
(a) HDPE
(b) LDPE
(c) teflon
(d) orlon
Answer:
(b) LDPE

Question 81.
Which one of the following catalyst is used in the preparation of high density polyethylene?
(a) benzoyi peroxide
(b) zeigler natta catalyst
(c) ammonium per sulphate
(d) hydrogen peroxide
Answer:
(b) zeigler natta catalyst

Question 82.
Identify the zeiglar natta catalyst.
(a) TiCI4 + (C2H5)3AI
(b) (C2H5)4Pb + TiCl4
(c) AICl3 + HCI
(d) ZnCI2 + Cone. HCI
Answer:
(a) TiCI4 + (C2H5)3AI

Question 83.
Which of the following is used to make bottles and pipes?
(a) LDPE
(b) Terylene
(c) PVC
(d) HDPE
Answer:
(a) LDPE

Question 84.
Which polymer is used in preparing non-sticking utensils?
(a) orlon
(b) PAN
(c) teflon
(d) HDPE
Answer:
(c) teflon

Question 85.
Which one of the following is used as a substitute of wool for making blankets, sweaters?
(a) orlon
(b) terylene
(c) polyester
(d) nylon
Answer:
(a) orlon

Question 86.
What are the raw materials required for the manufacture of Nylon 6, 6?
(a) caprolactam + hydrazine
(b) adipic acid + hexa methylene diamine
(c) methanal + ammonia
(d) phenol + methanal
Answer:
(b) adipic acid + hexa methylene diamine

Question 87.
Which one of the following is not a condensation polymer?
(a) nylon 6, 6
(b) nylon 6
(c) polyethylene
(d) terylene
Answer:
(c) polyethylene

Question 88.
Which one is used in the manufacture of nylon-6?
(a) adipic acid + hexamethylene diamine
(b) succinic acid + hexamethylene tetramine
(c) ∈-amino carproic acid
(d) adipic acid + hexamethylene tetramine
Answer:
(c) ∈-amino carproic acid

Question 89.
Which one of the following is the other name of nylon 6, 6?
(a) poly urethane
(b) urotropine
(c) poly caprolactum
(d) poly hexametheylene adipamide
Answer:
(d) poly hexametheylene adipamide

Question 90.
Which one of the following is used in the manufacture of tyrecards fabrics?
(a) nylon 6, 6
(b) nylon 6
(c) orlon
(d) dacron
Answer:
(b) nylon 6

Question 91.
What are the raw materials required for the manufacture of terylene?
(a) ethylene glycol + terephthalic acid
(b) phthalic auhydride + phenol
(c) adipic acid + hexamethylene diamine
(d) phenol + methanal
Answer:
(a) ethylene glycol + terephthalic acid

Question 92.
Name the catalyst used in the preparation of terylene?
(a) zeiglar natta catalyst
(b) zincacetate + antimony oxide
(c) benzoyi peroxide
(d) ammonium persuiphate
Answer:
(b) zincacetate + antimony oxide

Question 93.
Which one of the following is used as glass reinforcing material in safety helmets?
(a) nylon
(b) bakelite
(c) terylene
(d) orlon
Answer:
(c) terylene

Question 94.
What are the raw materials required for the manufacture of bakelite?
(a) ethane 1, 2 – diol + benzene 1, 4 – dicarboxylic acid
(b) phenol + methanal
(c) adipic acid + hexamethylene diamine
(d) isoprene + methanal
Answer:
(b) phenol + methanal

Question 95.
Linear polymer of phenol formal dehyde is called
(a) novolac
(b) bakelite
(c) terylene
(d) orlon
Answer:
(a) novolac

Question 96.
Which one of the following is used to prepare combs and pens?
(a) navolac
(b) soft bakelite
(c) hard bakelite
(d) neoprene
Answer:
(a) navolac

Question 97.
Which one of the following thermo setting plastic is used in paints?
(a) melamine
(b) hard bakelite
(c) navolac
(d) soft bakelite
Answer:
(c) navolac

Question 98.
Which one of the following is used for making unbreakable crockery?
(a) phenol formal dehyde
(b) melamine formal dehyde
(c) urea formal dehyde
(d) navolac
Answer:
(b) melamine formal dehyde

Question 99.
What are the raw materials required to prepare Buna – S rubber?
(a) phenol + methanal
(b) melamine + methanal
(c) styrene + butadiene
(d) adipic acid + methanal
Answer:
(c) styrene + butadiene

Question 100.
Which one of the following element is used in vulcanization of rubber?
(a) oxygen
(b) nitrogen
(c) carbon
(d) sulphur
Answer:
(d) sulphur

Question 101.
Which one of the following is a natural rubber?
(a) Buna-S
(b) Buna-N
(c) cis – 1, 4 – poly isoprene
(d) neoprene
Answer:
(c) cis – 1, 4 – poly isoprene

Question 102.
The raw material is used in the manufacture of ieoprene?
(a) isoprene
(b) chloroprene
(c) 1, 3 – buta diene
(d) vinyl chloride
Answer:
(b) chloroprene

Question 103.
Which one of the following rubber is used in the manufacture of chemical container and conveyer belts?
(a) Buna – N
(b) neo prene
(c) Buna – S
(d) poly isoprene
Answer:
(b) neo prene

Question 104.
The raw materials required for the manufacture of Buna – N are …………..
(a) acrylonitrile + Buta – 1, 3 – diene
(b) chloro prene + buta – 1, 3 – diene
(c) terephthalic acid + ethane 1, 2 – diol
(d) phenol + methanal
Answer:
(a) acrylonitrile + Buta – 1, 3 – diene

Question 105.
Which of the following are required to prepare Buna – S?
(a) vinyl cyanide + 1, 3 – butadiene
(b) chioro prene + buta -1, 3 – diene
(c) buta – 1, 3 – diene + styrene
(d) isoprene + styrene
Answer:
(c) buta – 1, 3 – diene + styrene

Question 106.
Which of the following used in medical field such as surgical sutures, 1asma substitute?
(a) PHBV
(b) PLA
(c) PCE
(d) all the above
Answer:
(d) all the above

Question 107.
Which one of the following is not an example of biodegradable plastic?
(a) polyhydroxy butyrate
(b) poly glycollic acid
(c) polythene
(d) poly caprolactone
Answer:
(c) polythene

Question 108.
Which of the following is an example for bio degradable plastic?
(a) polystyrene
(b) poly vinyl chloride
(c) bakelite
(d) polylactic acid
Answer:
(d) polylactic acid

Question 109.
Which one of the following is used in orthopaedic devices and in controlled release of drugs?
(a) PHB
(b) PHBV
(c) PGA
(d) PLA
Answer:
(b) PHBV

Question 110.
Glycine and e-amino caproic acid polymenses to give …………..
(a) glycyl amine
(b) nylon 6, 6
(c) Nylon – 2 Nylon 6
(d) orlon
Answer:
(c) Nylon – 2 Nylon 6

Question 111.
Which one of the following is used in making automobiles and foot wear?
(a) Bun – S
(b) Buna – N
(c) natural rubber
(d) neoprene
Answer:
(a) Bun – S

Question 112.
Which one of the following is used as an insulator and making conveyor belts?
(a) terylene
(b) orlon
(c) neoprene
(d) Buna – N
Answer:
(c) neoprene

Question 113.
Which type of nylon is used in making brushes, synthetic fibres, parachute, ropes and carpets?
(a) nylon – 2
(b) nylon – 6
(c) nylon 6,6
(d) nylon – 2, nylon 6
Answer:
(c) nylon 6,6

Question 114.
Which one is used in making non-breakable cups and laminated sheets?
(a) bakelite
(b) urea formaldehyde
(c) PHBV
(d) teflon
Answer:
(b) urea formaldehyde

Question 115.
Which of the polymer is used in making fibres, safety belts, lyre cords and ropes?
(a) terylene
(b) orlon
(c) Nylon
(d) bakelite
Answer:
(a) terylene

Question 116.
Identify the monomer of nylon – 2.
(a) adipic + Hexamethylene tetramine
(b) caprolactam
(c) vinyl chloride
(d) chioroprene
Answer:
(b) caprolactam

Question 117.
Which of the following is a fibre?
(a) nylon
(b) neoprene
(c) PVC
(d) bakelite
Answer:
(a) nylon

Question 118.
Identify the food preservative which is most commonly used by food producers?
(a) sodium cloride
(b) sodium sulphate
(c) baking soda
(d) benzoic acid
Answer:
(a) sodium cloride

Question 119.
Which of the following act as an antiseptic and disinfectant respectiely?
(a) 0.2% phenol, 1% phenol
(b) 1% phenol, 0.2% phenol
(c) 2% phenol, 20% phenol
(d) 20% phenol, 2% phenol
Answer:
(a) 0.2% phenol, 1% phenol

Question 120.
Identify the narcotic which is used as an analgesic.
(a) phenol
(b) equanil
(c) morphine
(d) cetrizine
Answer:
(c) morphine

Question 121.
What type of drug pencillin is?
(a) anaesthetic
(b) antibiotic
(c) antipyretic
(d) analgesic
Answer:
(b) antibiotic

Question 122.
Ranitidine is used as an …………
(a) antioxidant
(b) antiseptic
(c) antacid
(d) antibiotic
Answer:
(c) antacid

Question 123.
Aspirin is chemically named as ………….
(a) methyl salicylate
(b) ethyl salicylate
(c) o – hydroxy benzoic acid
(d) acetyl salicylic acid
Answer:
(d) acetyl salicylic acid

Question 124.
Which of the following can be used an analgesic without causing addiction and any modification?
(a) morphine
(b) n – acetyl paraminophenol
(c) diazepam
(d) tetra hydro catenol
Answer:
(c) diazepam

Question 125.
Tranquilisers are substances used for the treatment of ……………..
(a) cancer
(b) AIDS
(c) mental diseases
(d) blood infection
Answer:

Question 126.
Which of the following represents a synthetic detergent?
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-12
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-13

Question 127.
Which of the following represents a soap?
(a) C17H35COOk
(b) C17H35COOH
(c) C15H31COOOH
(d) (C17H35COO)2Ca
Answer:
(a) C17H35COOk

Question 128.
Which of the following drug is an analgesic?
(a) iodex
(b) valium
(c) analgin
(d) quinine
Answer:
(c) analgin

Question 129.
An antipyretic is …………
(a) chioro quinine
(b) paracetamol
(c) morphine
(d) ranitidine
Answer:
(b) paracetamol

Question 130.
Streptomycin is effective in the treatment of ……………
(a) tuberculosis
(b) malaria
(c) typhoid
(d) cholera
Answer:
(a) tuberculosis

Question 131.
A drug effective in the treatment of pneumonia, bronchitis etc is ………………….
(a) streptomycin
(b) aspirin
(c) penicillin
(d) paracetamol
Answer:
(c) penicillin

Question 132.
The substances which affect the central nervous system and induce sleep are called ………………..
(a) tranquilizers
(b) analgesics
(c) antioxidants
(d) antipyretic
Answer:
(a) tranquilizers

Question 133.
The correct structure of the drug paracetamol is ……………
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-14
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-15

Quesiton 134.
Which of the following acts as an antioxidant in edible oils?
(a) Vitamin B
(b) Vitamin C
(c) Vitamin D
(d) Vitamin E
Answer:
(d) Vitamin E

Question 135.
Which of the following is an antidiabatic drug?
(a) insulin
(b) inulin
(c) chioroquine
(d) aspirin
Answer:
(a) insulin

Question 136.
Which of the following terms means pain killer?
(a) antibiotics
(b) analgesic
(c) antiseptic
(d) antioxidant
Answer:
(b) analgesic

Question 137.
The artificial sweetener containing chlorine that has the appearance and taste as the sugar and is stable at cooking temperature is …………….
(a) aspartame
(b) saccharin
(c) sucralose
(d) alitame
Answer:
(c) sucralose

Question 138.
The role of phosphate in detergent powder is …………..
(a) control pH level of the detergent water mixture
(b) remove Ca2+ and Mg2+ ions from water that causes hardness of water
(c) provide whiteness to the fabric
(d) more soluble in soft water
Answer:
(b) remove Ca2+ and Mg2+ ions from water that causes hardness of water

Question 139.
Which among the following is not an antibiotic?
(a) erythromycin
(b) oxytocin
(c) penicillin
(d) tetracycline
Answer:
(b) oxytocin

Question 140.
Commonly used antiseptic ‘dettoP is a mixture of …………..
(a) O – chloro phenozylenol + terpeneol
(b) O – cresol + terpenol
(c) phenol + terpeneol
(d) chioroxylenol + terpeneol
Answer:
(d) chioroxylenol + terpeneol

II. Fill in the blanks.

  1. The specific treatment of a disease using medicine is known as ……………..
  2. The drug which interacts with macro molecular targets such as proteins to produce a therapautic and useful biological response is called ………………
  3. ……………..is a substance that is used to modifS’ or explore physiological systems for the benefit of the recepient.
  4. Higher the value of …………….. safer is the drug
  5. The medicines that have ability to kill the pathogenic bacteria are grouped as ……………..
  6. Proteins which act as biological catalysts are called …………….. and those which are important for communication systems are called ……………..
  7. Many bacteria need …………….. in order to produce an important coenzyme, folic acid
  8. When adenosine binds to the adenosine receptors, it induces ……………..
  9. Morphine that used as a pain killer suppress the …………….. that causes pain.
  10. Histames stimulate the secretion of …………….. by activating the receptor in the stomach wall.
  11. …………….. acts on the central nervous system by blocking the neuro transmitter dopamine in the brain.
  12. …………….. reduce the pain without causing impairment of consciousness.
  13. …………….. are drugs that used to reduce fever and prevent platelet coagulation
  14. …………….. relieve pain and produces steeps and they are additive.
  15. …………….. neutralise the acid in the stomach that causes acidity.
  16. …………….. cause a controlled and reversible loss of consciousness by affecting central nervous SyStem.
  17. …………….. anaesthetics are often used for major surgical procedures.
  18. …………….. provide relief from allergic effects.
  19.  …………….. inhibits bacterial cell wall biosynthesis.
  20. …………….. inhibits bacterial enzyme DNA gyrase.
  21. …………….. stop or slow down the growth of microorganisms applied to living tissues.
  22. …………….. stop or slow down the growth of microorganisms used on inanimate objects.
  23. The substances which are not naturally a part of the food and added to improve the quality of food are called ……………..
  24. Flavouring agents added to food enhance the …………….. of the food.
  25. …………….. are substances which retard the oxidative deteriorations of food.
  26. Synthetic compounds which imprint a sweet sensation and possess no or negligible nutritional value are called ……………..
  27. Chemically soap is a …………….. or …………….. salt of higher fatty acids.
  28. …………….. is a sodium salt alkyl hydrogen sulphate or alkyl benzene suiphonic acid.
  29. The quality of soap is described interrns of …………….. and the …………….. quantity in the soap better is its quality
  30. …………….. become soft on heating and hard on cooling and they can be remoulded.
  31. …………….. donot become soft on heating but set to an infusible mass upon heating.
  32. In the manufacture of Teflon. the monomer used is ……………..
  33. …………….. is used as a substitute of wool for making blankets, sweaters
  34. …………….. is a monomer which polymerises to give nylon – 6.
  35. Para hydroxyl methyl phenols poíymerises to give a linear polymer called ……………..
  36. The monomer of natural rubber is ……………..
  37. For the vulcanization of natural rubber …………….. is used and heated to 100° 150°C.
  38. …………….. polymers are used in medical field such as surgical sutures, plasma substitute.
  39. A drug that binds to the receptor site should inhibit its natural function is called ……………..
  40. …………….. reduces fever by causing the hypothalamus to override a prostaglandin-induced increase in temperature.

Answer:

  1. chemotheropy
  2. medicine
  3. Drug
  4. therapeutic index
  5. antibiotics
  6. enzymes, receptors
  7. PABA
  8. sleepiness
  9. neuro transmitters
  10. HCI
  11. Tranquilizers
  12. Analgesics
  13. Antipyretic
  14. Narcotic Analgegics (or) opioids
  15. Antacids
  16. General anaesthetics
  17. Inhalational general
  18. Antihistamines
  19. Antimicrobials
  20. Fluoroquinolones
  21. Antiseptic
  22. Disinfectants
  23. food additives
  24. aroma
  25. Antioxidant
  26. artificial sweatness
  27. sodium, potassium
  28. Detergent
  29. TFM, TFM
  30. Thermoplastic
  31. Thermosetting
  32. tetra fluoroethylene
  33. orIon (or) PAN
  34. Caprolactam
  35. novolac
  36. cis – isoprene (OR) 2 – methyl buta- 1, 3 – diene
  37. sulphur
  38. Biodegradable
  39. antagonists
  40. Non steroidal anti inflammatory drugs (or) NSAIDS

III. Match the following

Question 1.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-16
Answer:
(a) 2 4 1 3

Question 2.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-17
Answer:
(a) 2 4 1 3

Question 3.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-18
Answer:
(a) 4 3 1 2

Question 4.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-19
Answer:
(a) 3 4 2 1

Question 5.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-20
Answer:
(a) 3 2 4 1

Question 6.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-21
Answer:
(a) 2 3 4 1

Question 7.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-22
Answer:
(b) 3 4 1 2

Question 8.

Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-23
Answer:
(a) 2 4 1 3

Question 9.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-64
Answer:
(a) 3 4 1 2

Question 10.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-65
Answer:
(a) 2 4 1 3

Question 11.

Answer:
(a) 2 4 1 3

Question 12.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-24
Answer:
(a) 3 4 1 2

Question 13.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-25
Answer:
(a) 4 1 2 3

Question 14.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-26
Answer:
(a) 2 4 1 3

Question 15.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-27
Answer:
(b) 2 3 4 1

Question 16.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-28
Answer:
(a) 2 3 4 1

IV. Assertion and reasons.

Question 1.
Assertion(A): Higher the value of therapeutic index, safer the drug.
Reason (R): Therapeutic index is defined as the ratio between the maximum tolerated dose of a drug and the minimum curative dose.
(a) Both A and R are correct and R Is the correct explanation of A.
(b) Both A and R are correct but R dOes not explains A.
(c) A is correct but R is wrong.
(d) A is.wrong but R is correct.
Answer:
(a) Both A and R are correct and R Is the correct explanation of A.

Question 2.
Assertion(A): In all living systems, the biochemical reactions are catalysed by enzymes. This principle is applied to kill many pathogens.
Reason (R): The enzyme actions are highly essential for normal functioning of the system.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R explains A.

Question 3.
Assertion(A): The drugs acts as an inhibitor to the enzyme catalyst.
Reason (R): A drug molecule that has a similar geometry (shape) as the substrate is administered, it can also bind to the enzyme and inhibit its activity.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R explains A.

Question 4.
Assertion(A): Aspirin is an antipyretic and useful in the prevention of heart attacks.
Reason (R): Aspirin reduces fever and also prevent platelet coagulation.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 5.
Assertion(A): Opioids produces coma and even death.
Reason (R): Opioids releive pain and produce sleep and drugs are addictive and also poisonous in nature.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R explains A.

Question 6.
Assertion(A): Milk of magnesia and aluminium hydroxide are usually used as antacids.
Reason (R): Mg(OH)2 and Al(OH)3 are weak bases and they neutralise the acid in the stomach that causes acidity.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R explains A.

Question 7.
Assertion(A): Procaine and Lidocaine are local anaesthetics and cause loss of sensation in the area in which it is applied without losing consciousness.
Reason (R): They block pain perception that is transmitted via peripheral nerve fibres to the brain.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R explains A.

Question 8.
Assertion(A): Antioxidant such as butyl hydroxy toluene (BHT) and butylated hydroxy anisole (BHA) are added as good additives.
Reason (R): Antioxidants retard the oxidative deterioration of food which contain fat and oils is easily oxidised and turn rancid.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 9.
Assrtion(A): Saccharin, sucralose are artificial sweeteners.
Reason (R): Synthetic compounds which imprint a sweet sensation and possess no or negligible nutritional value are called artificial sweeteners.
(a) Both A and R are correct and R does not explains A.
(b) Both A and R are correct and R explains A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(b) Both A and R are correct and R explains A.

Question 10.
Assertlon(A): Sulphur dioxide and suiphites are also used as food additive.
Reason (R): They act as antimicrobial agents, antioxidant and enzyme inhibitors.
(a) Both A and R are correct but R does not explains A.
(b) Both A and R are correct and R explains A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(b) Both A and R are correct and R explains A.

Question 11.
Asscrtion(A): During soap preparation, common salt is added to the reaction mixture.
Reason (R): Common salt decreases the solubility of soap and it helps to precipitate out from the aqueous solution.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R explains A.

Question 12.
Assertion(A): Higher the TFM quantity in the soap, better is its quality.
Reason (R): The quality of the soap is described in terms of total fatty matter (TFM value). Grade I soap should have 76% minimum TFM value.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R explains A.

Question 13.
Assertion(A): Natural rubber becomes strong and elastic when heated with sulphur.
Reason (R): Natural rubber is mixed with 3 – 5% sulphur and heated at 100 – 150°C causes cross linking of the cis – 1, 4 – polyisoprene chains through disulphide – s – s bonds.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R explains A.

Question 14.
Assertion(A): Artificial sweeteners are added to the food to control the intake of calories.
Reason (R): Most of the artificial sweeteners are inert and do not metabolise in the body,
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R explains A.

Question 15.
Assertion(A): Penicillin (G) is an antihistamine.
Reason (R): Penicillin G is effective against gram positive as well as gram negative bacteria.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(d) A is wrong but R is correct.

Question 16.
Assertlon(A): Enzymes have active sites that hold substrate molecule for a chemical reaction.
Reason (R): Drugs compete with natural substate by attaching covalently to the active site of enzyme.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(c) A is correct but R is wrong.

Question 17.
Assertion(A): Transparent soaps are made by dissolving soaps in ethanol.
Reason (R): Ethanol made things invisible.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R Is wrong.
(d) A is wrong but R is correct.
Answer:
(c) A is correct but R Is wrong.

Question 18.
Assertion(A): Sodium chloride is added to precipitate soap after saponification.
Reason (R): Hydrolysis of esters of long chain fatty acids by alkali produces soap in colloidal form.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R explains A.

Question 19.
Assertlon(A): Aspirin has antipyretic properties.
Reason (R): Aspirin gives relief from pain.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R explains A.

Question 20.
Assertlon(A): Bithional is added to soap as an antiseptic.
Reason (R): Bithional is a suipha drug and destroy bacteria.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R explains A.

VI. Find out the correct pair.

Question 1.
Ampicillin, amoxicillin, methiceillin, cetrizine, cephalosporin.
Answer:
Cetrizine. It is an antihistamine whereas others belongs to penicillin group.

Question 2.
Aluminium hydroxide, magnesium hydroxide, erythromycin, cimetidine, ranitidine.
Answer:
Erythromycin. It is antimicrobial whereas others are antacids.

Question 3.
Halo peridol, clozapine, aiprazolam, aspirin, diazepam.
Answer:
Aspirin. It is an analgesic and antipyretic whereas others are anaesthetics.

Question 4.
Acetamino phenol, ibuprofen, aspirin, morphine.
Answer:
Morphine. It is an opioids (narcotic analgesic) whereas others are non narcotic analgesics.

Question 5.
Morphine, heroin, hydrocodone, codeine, ibuprofen.
Answer:
Ibuprofen. It is a non narcotic analgesic whereas others are narcotic analgesics.

Question 6.
Procaine, lidocaine, cemitidine, propofol, iso flurane.
Answer:
Ccmitidine. It is an antacid whereas others are anaesthetics.

Question 7.
Omeprazole, rabeprazole, iso flurane, ranitidine, cemitidine.
Answer:
Isoflurane. It is an anaesthetic whereas others are antacids.

Question 8.
Cetrizine, levocetrizine, trefenadine, ampicillin, desloratatide.
Answer:
Ampicillin. It is antimicrobial whereas others are antihistamines.

Quesiton 9.
Penicillin, ampicillin, cephalosorins, hydrogen peroxide, carbapenems.
Answer:
Hydrogen peroxide. it is an antiseptic where as other are antimicrobials.

Question 10.
Hydrogen peroxide, povidone – iodine, chlorine compounds, benzalkonium chloride.
Answer:
Chlorine compounds. It is a disinfectant whereas others arc antiseptic.

Question 11.
Ethynylestradiol, menstranol, hydrogen peroxide, norethindrone, norethynodrel.
Answer:
Hydrogen peroxide. It is an antiseptic and a disinfectant whereas otheres are antifertility drugs.

Question 12.
Sodium benzoate, salt of sorbic acid, acetic acid, sodium bi carbonate, sodium meta suiphite.
Answer:
Sodium bi carbonate. It is a baking soda whereas others are food preservatives.

Question 13.
BIIT, BHA, SO2, Vitamin E, sorbitol.
Answer:
Sorbitol. It is a sugar substituent where as others are antioxidants.

Question 14.
Saccharin, butyl hydroxy toluene, aspartane, sucralose, alitaine.
Answer:
Butyl hydroxy toluene, It is an antioxidant where as others are artificial sweetening agents.

Question 15.
Cellulose, polyester, silk.
Answer:
Polyester. It is a synthetic polymer whereas others are natural polymer.

Question 16.
PVC, polythene, LDPE, cellulose, HDPE, bakelite
Answer:
Cellulose, It is a natural polymer whereas others are synthetic polymers.

Question 17.
Polythcne, PVC, Bakelite, polystrene.
Answer:
Bakelite. It is thermosetting plastic whereas others are thermoplastic.

Question 18.
Nylon 66, polyethylene, PVC, teflon.
Answer:
Nylon 66. It is a condensation polymer whereas others are addition polymers.

Question 19.
Neoprene, bakelite, Buna – S, Buna – N.
Answer:
Bakelite. It is a thermosetting plastic whereas others are synthetic rubber.

Question 20.
Nylon 66, Nylon 6, terylene, teflon, bakelite, melamine.
Answer:
Teflon. It is an additional polymer whereas others are condensation polymers.

Samacheer Kalvi 12th Chemistry Chemistry in Everyday Life 2 mark Questions and Answers

Question 1.
Define the term

  1. medicine
  2. chemotherapy

Answer:
1. Medicine:
The drug which interacts with macromolecular targets such as proteins to produce a therapeutic and useful biological response is called medicine.

2. Chemotherapy:
The specific treatment of a disease using medicine is known as chemotherapy.

Question 2.
Define the term therapeutic index.
Answer:
1. Therapeutic index is defined as the ratio between the maximum tolerated dose of a drug (above which it becomes toxîc) and the minimum curative dose (below which the drug is ineffective).

2. Higher the value of therapeutic index, safer is the drug.

Question 3.
Write about the classification of drugs based on the target system.
Answer:
1. In this classification, the drugs are grouped based on the biological system that they target in the recepient. For example, the antibiotics streptomycin and erthyromycin inhibit the protein synthesis in bacteria and are classified in the same group.

2. However their mode of action is different. Streptomycin inhibits the initiation of protein synthesis, while erythromycin prevents the incorporation of new amino acids to the protein.

Question 4.
Explain about the classification of drug based on the site of action.
1. The drug molecule interacts with biomolecules such as enzymes, receptors which are referred as drug targets. The drug is classified based on the drug target with which it binds.

2. This classification is highly specilic compared to others. These compounds often have a common mechanism of action, as the target is the same.

Question 5.
What are

  1. antagonists
  2. agonists.

Answer:

  1. The drugs which binds to the receptor site and inhibit its natural function are called antagonists.
  2. There are drugs which mimic the natural messenger by switching on the receptor. Those type of drugs are called agonists.

Question 6.
What is the difference between an agonist and antagonist?
Answer:

  1. Agonist and antagonist act in opposite directions. Agonist is a substance which combines with cell receptor to produce some reaction that is typical for that substance.
  2. On the other hand antagonist is the chemical which opposes or reduces the natural function.

Question 7.
Explain the action of agonist and antagonist with proper example.
Answer:
When adenosine binds to the adenosine receptors, it induces sleepiness. So adenosine is an agonist. On the other hand, the antogonist drug coffeine binds to the adenosine receptor and makes it inactive. This results in the reduced sleepiness (wakefulness).

Question 8.
Why ranitine is a better antacid than magnesium hydroxide?
Answer:
To treat acidity, weak base such as magnesium hydroxide is used. But this weak base make the stomach alkaline and trigger the production of much acid. This treatment only relieves the symptoms and does not control the cause. But ranitine stimulate the secretion of HCI by activating the receptor in the stomach wall which binds the receptor and inactivate them. So ranitine is a better antacid than magnesium hydroxide.

Question 9.
What is meant by non-steroidal anti inflammatory drugs? Give example.
Answer:
Non – steroidal anti inflammatory drugs reduces fever by causing the hypothalamus to override a prostaglandin – induced increase in temperature. eg., ibuprofen.

Question 10.
What are narcotic analgesics? Give examples.
Answer:

  1. Narcotic analgesics are opioids that relieve pain and produce sleep. These drugs are addictive. In poisonous dose, these produces coma and ultimately death. eg, morphine, codeine,
  2. These drugs are used for short term or long term relief of severe pain. Mainly used for post operative pain. Pain of terminal cancer.

Question 11.
What are general anaesthetics? Give example.
Answer:

  1. General anaesthetics are drugs cause a controlled and reversible loss of consciousness by affecting central nervous system. e.g., propofol, iso flurane.
  2. They are often used for major surgical procedures.

Question 12.
What are local anaesthetics? Give example. Mention its uses.
Answer:

  1. Local anaesthetics cause loss of sensation in the area in which it is applied without losing consciousness. They block pain perception that is transmitted via peripheral nerve fibre to the brain. e.g., procaine, lidocaine
  2. They are often used during minor surgical procedures.

Question 13.
Draw the structure of propofol? Mention its use.
Answer:
Propofol structure:
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-29

Question 14.
What are antihistamines? Give example and mention its use.
Answer:

  1. Antihistamines block histamine release from histamine – 1 receptors.
  2. eg., cetirizine, terfenadine, levocetirizine.
  3. It is used to provide relief from the allergic effects.

Question 15.
What are antimicrobials? Mention its function and its uses.
Answer:

  1. Antimicrobials inhibits bacterial cell wall biosynthesis.
  2. e.g., penicillin, ampicillin.
  3. It is used to treat skin infections, dental infections, ear infections, respiratory tract infections. Pneumonia, urinary tract infections and gonorrhoea.

Question 16.
Draw the structure of penicillin? Give its use.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-30
Penicillin is used to treat all type of infections pneumonia, urinary tract infections.

Question 17.
Draw the structure of ampicillin
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-31

Question 18.
Write a note about macrolids.
Answer:

  1. Macrolids targets bacterial ribosomes and prevent protein production. e.g., erythromycin, azithromycin
  2. It is used to treat respiratory tract infections, genital, gastro intestinal tract and skin infections.

Question 19.
What are fluoroquinolones? Give its function and uses.
Answer:

  1. Fluoro quinolones inhibits bacterial enzyme DNA gyrase.
  2. e.g., clinafloxacin, ciprofloxacin
  3. It is used to treat urinary tract infections, skin infections and respiratory infections, pulmonary infections in cystic fibrosis.

Question 20.
What are tetracydines? Mention its function and uses.
Answer:

  1. Tetracyclines inhibit the bacterial protein synthesis via interaction with the 30 S subunit of the bacterial ribosome. eg., doxycycline, minocycline.
  2. It is used in the treatment of peptic ulcer disease, infections of the respiratory tract, cholera.

Question 21.
What are aminoglycosides? Give its function and uses.
Answer:

  1. Aminoglycosides bind to the 30 S subunit of the bacterial ribosome, thus stopping bacteria from making proteins.
  2. It is used to treat infections caused by gram negative bacteria.

Question 22.
What are food additives? Give example.
Answer:

  1. The substances which are not naturally a part of the food and added to improve the quality of food are called food additives.
  2. e.g., Aroma compounds, antioxidants, preservatives, stabilizers, food colours, buffering substances are food additives.

Question 23.
Explain about antioxidants.
Answer:

  1. Antioxidants are substances which retard the oxidative deteriotations of food. Food containing fats and oils is easily oxidised and turn rancid, .
  2. To prevent the oxidation of fats and oils, chemical BHT (butyl hydroxy toluene), BHA (butylated hydroxy anisole) are added as antioxidants.
  3. These materials readily undergo oxidation by reacting with free radicals generated by the oxidation of oils there by stop the chain reaction of oxidation of food.
  4. Sulphur dioxide, suiphites are also used as antioxidant and also act as antimicrobial agents and enzyme inhibitors.

Question 24.
What are sugarsubstituents? Give example.
Answer:
The compounds that are used like sugars for sweetening, but are metabolised without the influence of insulin are called sugar substituents. e.g., sorbitol, xylitol, mannitol.

Question 25.
What are artificial sweetening agents? Give example.
Answer:
Synthetic compounds which imprint a sweet sensation and possess no or negligible nutritional value are called artificial sweeteners. e.g., saccharin, aspartame, sucralose, alitame.

Question 26.
Define TFM value.
Answer:

  1. The quality of a soap is described in terms of total fatty matter (TFM value). It is defined as the total amount of fatty matter that can be separated from a sample after spliting with mineral acids.
  2. Higher the TFM value in the soap, better is its quality.
  3. As per BIS standards, Grade I soaps should have 76% minimum TFM value.

Quesiton 27.
Write a note about natural rubber and give Its structure.
Answer:
1. Rubber is a naturally occuring polymer. It is obtained from the latex that excludes from cuts in the bark of rubber tree.

2. The monomer unit of natural rubber is cis – iso prene (2 – methyl buta – 1,3 – diene). Thousands of isoprene units are linearly linked together in natural rubber. NaturaL rubber is not so strong (or) elastic. The properties of natural rubber can be modified by the process called vulcanization.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-32

Question 28.
How is neoprene prepared? Give its use.
Answer:
1. The free radical polymerisation of the monomer 2 – chloro buta 1,3 – diene (chioroprene) gives neoprene.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-33

2. It is used in the manufacture of chemical container, conveyer belts.

Question 29.
How Is Buna – N prepared? Give its use.
Answer:
1. Buna – N is prepared by the polymerisation of acrylonitile and buta – 1, 3 – diene
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-34

2. It is used in the manufacture of hoses and tank linings.

Question 30
How would you prepare Buna – S? Give its use.
Answer:
Buna – S is prepared by the polymerisation of buta – 1, 3 – diene and styrene in the ratio of 3 : 1 in the presence of sodium.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-35

Uses:
It is used in making pneumatic tires in shoe heels and soles, and in gaskets.

Question 31.
How will you prepare PHBV? Give its use?
Answer:
1. The biodegrable polymer PHBV (Poly hydroxy butyrate-co hydroxyl valerate) is prepared by the polymerisation of monomers 3 – hydroxy butanoic acid and 3 – hydroxy pentanoic acid.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-36

2. It is used in orthopacdic devices añd in controlled release of drugs.

Question 32.
How would you prepare Nylon – 2 – Nylon – 6 polymers?
Answer:
Nylon – 2 – Nylon 6 is a co polymer which contains polyamide linkages. It is obtained by the condensation polymerisation of monomers glycine and E-amino caproic acid.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-37

Question 33.
What are natural and synthetic polimers? Give two examples of each type.
Answer:
Natural polymers:
Polymers which are found in nature, i.e., in animal and plants are called natural polymers. For example, proteins, starch, cellulose etc.

Synthetic polymers:
Man – made polymers are called synthetic polymers. For example plastics, synthetic fibres.

Question 34.
Distinguish between the terms homopolymer and copolymer and give an example of each.
Answer:
Homopolyers:
Polymers whose repeating structural units are dervied from only one type of monomer units are called homopolymers. For example, polythene, PVC, PAN etc.

Copolymers:
Polymers whose repeating units are derived from two or more types of monomer molecules are called co-polymers. For example, l3una – S, Buna – N, Nylon 6, 6 etc.

Question 35.
How can you differentiate between addition and condensation polymerisation?
Answer:
Addition polymerisation:
In this type of polymerisation, a large number of molecules of same or different monomers simply add to the other unit, leading to the formation of macromolecule. Addition polymerisation generally occurs among molecules containing double and triple bonds.

Condensation polymerisation:
In this type of polymerisation two or more bifunctional molecules undergo a series of independent condensation reactions usually with the elimination of simple molecules like water, alcohol, ammonia etc.

Question 36.
What are the monomeric repeating units of Nylon – 6 and Nylon 6, 6?
Answer:
Nylon 6 – Caprolactam. Nylon 6,6 – Adipic acid and Hexamethylenediamine

Question 37.
Write the names and structure of the monomers of the following polymers:

  1. Buna – S
  2. Buna – N
  3. Dacron
  4. Neoporene

Answer:
1. Butadiene, CH2 = CH – CH = CH2 ; Styrene, C6H5 – CH = CH2

2. Butadiene, CH2 = CH – CH = CH2 ; Acrylonitrile, Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-38

3. Terephthalic acid,Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-39 ; Ethylene glycol (Ethane – 1, 2 – diol)Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-40

4. Chloroprene,Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-41 ; 2 – Chloro – 1, 3 – butadine is the monomer of neoprene.

Question 38.
How is dacron obtained from ethylene glycol and terephthalic acid?
Answer:
Dacron is obtained by condensation polymerisation of ethylene glycol and terephthalic acid with the elimination of water molecules:
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-42

Question 39.
What is a biodegradable polymer? Give an example of a biodegradable aliphatic polyester.
Answer:
Polymers which disintegrate by themselves over a period of time due to environmental degradation by bacteria, etc. are called biodegradable polymers. Example: PHBV (poly hydroxy butrate – co – β hydroxyvalcrate)

Question 40.
What is the difference between elastomers and fibres? Give one example of each.
Answer:
Elastomers

  1. These are rubber like solids with elastic properties.
  2. These are held by the weak inter – molecular forces.
  3. Example: Buna-S and Buna-N.

Fibres

  1. These are th thread forming solids which possess high tensile strength and high modulus.
  2. These are held together by strong intermolecular forces like hydrogen bonding.
  3. Example: Nylon 6, 6 and polyesters (terylene)

Question 41.
What are thermoplastics and thermosetting polymers? Give one example of each.
Answer:
Thermoplastics:
Thermoplastics are linear polymers which can be repeatedly softened on heating and hardened on cooling and hence can be used again and again without any change in chemical composition and mechanical strength.

Thermosetting polymers:
Thermosetting polymers, are permanently setting polymers. On heating in a mould, they get hardened and set and cannot be softened again. This hardening on heating is due to cross linking between different polymeric chains which give rise to a three dimensional network solid. Example – Bakelite.

Question 42.
Differentiate between addition and condensation polymers based on the mode of polyrnerisation. Give one example of each type. 1
Answer:
Addition polymers

  1. They are formed by adding monomers to a growing polymer chaìn without loss of any molecule.
  2. They are formed from unsaturated compounds.
  3. Example: Polyethene, polypropene.

Condensation polymers

  1. They are formed by combining monomers together with the loss of small molecules like H2O, NH3, CO2 etc.
  2. Monomers have di or polyfunctional groups.
  3. Example: Nylon – 6, 6, Nylon – 6, Terylene.

Question 43.
Distinguish between ‘chain growth potymerisatlon and step growth polymerisation’ and give one example of each.
Answer:
Chain growth polymerisation

  1. Only one repeating unit is added at a time.
  2. Reaction is fast and polymer is formed at once. Example – polythene.

Step growth polymerisatlon

  1. Any two species present can react.
  2. Polymer is formed in gradual steps. Examply – Nylon-6, 6.

Question 44.
How are biopolymers more beneficial than synthetic polymers?
Answer:
Durability of synthetic polymers is advantageous, however it presents a serious waste disposable problem. In renewal of the disposable problem, biodegradable polymers are useful to us. Biopolymers arc safe in use. They disintegrate by themselves in biological system during a certain period of time by enzymatic hydrolysis and to some extent by oxidation and hence, are biodegradable. As a result, they do not cause any pollution.

Question 45.
Give the method of preparation of polyacrylonitrile?
Answer:
The addition polymerisation of acrylonitrile in the presence of a peroxide catalyst leads to the formation of polycrylonitrile. It is used as a substitute for wool in making fibres such as orlon or acrilan.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-43

Samacheer Kalvi 12th Chemistry Chemistry in Everyday Life 3 mark Questions and Answers

Question 1.
Draw the structures of

  1. Suiphanilamide
  2. p – nltro benzoic acid

Answer:
1. Suiphanilamide
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-44

2. p – nitro benzoic acid:
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-45

Question 2.
Draw the structure of

  1. Adenosine (Agonist)
  2. Caffeine (Antagonist)

Answer:
1. Adenosinc (Agonist)
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-46

2. Caffeine (Antagonist)
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-47

Question 3.
Explain about

  1. Analgesics
  2. Antlinflammatory drugs
  3. Antipyretlcs

Answer:
1. Analgesics:
They alleviate pain by reducing local inflammatory response. They reduce the pain without causing impairment of consciousness.
Example: Paracetamol (Crocin).

2. Anti inflammatory drug:
They are used for short term pain relief and for modest pain like head ache, muscle strain, bruising or arthritis.
Example: Ibuprofen, Aspirin.

3. Antipyretics:
These drugs have many effects such as reducing fever, and preventing platelet coagulation.
Example: Aspirin.

Question 4.
Explain about anaesthetics with their types.
Answer:
1. Local anaesthetics: It causes loss of sensation in the area in which it is applied without losing consciousness. They block pain perception that is transmitted via peripheral nerve fibres to the brain. Example: Procaine, Li do Caine. They are often used during minor surgical procedures.

2. General anaesthetics:
They cause a controlled and reversible loss of consciousness by affecting central nervous system.
Example: Propofol, Isoflurane. They are often used for major surgical procedures.

Question 5.
Draw the structure of

  1. procaine
  2. Lidocaine

Answer:
1. Procaine
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-48

2. Lidocaine
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-49

Question 6.
Explain about antacids?
Answer:

  1. Antacids neutralise the acid in the stomach that causes acidity.
  2. They are used to relieve burning sensation in the chest, throat area caused by acid reflux. Example – Milk of magnesia, alumminium hydroxide, Ranitidine, Cemitidino, Omeprazole, Rabeprazole.

Question 7.
Distinguish between Antiseptic and Disinfectants.
Answer:
1. Antiseptic:
They are the drugs used to stop (or) slow down the growth of micro organism and they are applied to living tissue (body). Example: H2O2.

2. Disinfectant:
They are the drugs used to stop or slow the growth of micro organism and they are applied on inanimate objects (non living surfaces). Example: Chlorine compounds.

Question 8.
What are the advantages of food additives?
Answer:

  1. Uses of preservatives reduce the product spoilage and extend the shelf-life of food.
  2. Addition of vitamins and minerals reduces the mall nutrient.
  3. Flavouring agents enhance the aroma of the food.
  4. Antioxidants prevent the formation of potentially toxic oxidation products of lipids and other food constituents.

Question 9.
Differentiate soap and detergents?
Answer:
Soap

  1. Soaps are sodium or potassium salt of long chain fatty acid.
  2. Soaps are made from animal (or) plant fats and oils.
  3. Soaps have lesser cleansing action.
  4. Soaps are bio degradable.
  5. Soaps are less effective in hard water.
  6. They have a tendency to form a scum in hard water.
  7. Example: Sodium palmitate.

Detergent

  1. Detergent is sodium salt of alkyl hydrogen sulphate or alkyl benzene suiphonic acid.
  2. Detergents are made from petrochemicals.
  3. Detergents have more cleansing action.
  4. Detergents are non – bio degradable.
  5. Detergents are more effective even in hard water.
  6. They do not form scum with hard water.
  7. Example: Sodium lauryl sulphate.

Question 10.
What is LDPE? Give its preparation and uses.
Answer:
1. LDPE is low density poiy ethylene. It is formed by heating ethene at 2000 to 300°C under oxygen as a catalyst. This reaction follows free radical mechanism. The peroxide formed from oxygen acts as a free radical initiator.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-50

2. LDPE is used as insulation for cables, making toys.

Question 11.
What is HDPE? Cive its preparation and use.
Answer:

  1. IIDPE is high density polyethylene. it is prepared by the polymerisation of ethylene at. 373k and 6 to 7 atm. using zeiglar Natta Catalyst)
  2. Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-51
  3. It is used to make bottles, pipes.

Question 12.
What is Orlon? Give its preparation and use.
Answer:
1. Orlon is poiy acrylonitrite (PAN). It is prepared by the addition of polymerisation of vinyl cyanide using a peroxide initiator.

2.Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-52

3. It is used as a substitute of wool for making blankets, sweaters etc.

Question 13.
How will you prepare Nylon 6,6.? Give its use.
Answer:
1. Nylon 6,6 can be prepared by mixing equimolar adipic acid and hexamethylene diaminc. With the elimination of water to form amide bonds.

2. Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-53

3. It is used in textiles, manufacture of cards.

Question 14.
How will you prepare Nylon – 6? Give its use.
1. Capro tactum on heating at 533k in an inert atmosphere with traces of water gives E amino caproic acid which polymerises to give Nylon 6.

2.Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-54

3. It is used in the manufacture of tyre cards, fabrics.

Question 15.
What is bakeite? How is it prepared? Give its uses.
Answer:
1. Bakelite is a thermo setting plastic. It is prepared from the monomers such as phenol and formaldehyde. The condensalion polymerisation take place in the presence of acid or base catalyst.

2. Phenol reacts with methanal to form ortho or para hydroxyl methyl phenols which on further reaction with phenol gives linear polymer called novolac. Novolac on further healing with formaldehyde undergoes cross linkages to form bakelite.

3.Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-55

4.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-56

  1. Novolac is used in paints.
  2. Soft bakelites are used in making glue for binding laminated wooden planks and in varnishes.
  3. Hard bakelites are used to prepare combs, pens.

Question 16.
How Is melamlue prepared? Give its use?
Answer:
Melamine and formaldehyde are the monomers. They undergo condensation polymerisation to form melamine formaldehyde resin.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-57
Uses : It is used in making unbreakable crockery.

Question 17.
How is urea formaldehyde prepared?
Answer:
It is formed by condensation polymerisation of the monomers urea and formaldehyde. Uses – it is used in decorative laminates, textiles, wrinkle resistant fabrics, paper and glue wood.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-58

Question 18.
Mention one use of each of the following:

  1. Ranitidine
  2. Paracetamol
  3. Tincture of iodine.

Answer:

  1. Rnitidine is used as an antacid.
  2. Paracetamol is used to bring down the body temperature during high fever.
  3. Tincture of iodine is used as an antiseptic. It is 2-3% solution of iodine in alcohol and water.

Question 19.
Describe the following with suitable examples:

  1. Preservatives
  2. Artificial sweetening agents.

Answer:
1. Preservatives:
Preservatives are the substances which are used to prevent spoilage of food due to microbial growth. Examples – Sodium benzoate, Common salt.

2. Artificial sweetening agents:
These are the chemical substances which are used to create sweet taste in food items in place of sugar.

Question 20.
Give one important use of each of the following:

  1. Bithional
  2. Chioramphenicol
  3. Streptomycin
  4. Paracetamol

Answer:

  1. Bithional is added to soap so as to impart antiseptic properties to the soap.
  2. Chioramphenicol is a broad spectrum antibiotic used in curing typhoid, meningitis.
  3. Streptomycin is used for the treatment of T.B (Tuberculosis).
  4. Paracetamol is an antipyretic used in bringing down temperature in high fever.

Question 21.
What are detergents? How are they classified? Why are detergents preferred over soaps?
Answer:
Detergents are suiphonate or hydrogen sulphate salts of long chain hydrocarbons containing 12-18 carbon atoms.
Types of detergents

  1. Cationic detergents
  2. Anionic detergents
  3. Non-ionic detergents

Advantages of detergents over soaps: Unlike soaps they work well even with hard water. They can work well even in acidic water. They are more effective than soaps.

Question 22.

  1. What class of drug is Ranitidine?
  2. If water contains dissolved Ca2+ ions, out of soaps and synthetic detergents, which will you use for cleaning clothes?
  3. Which of the following is an antisepctic? 0.2% phenol, 1% phenol.

Answer:

  1. It is an antacid.
  2. In this case we use synthetic detergents because it give foam with hard water.
  3. 0.2% solution of phenol acts as antiseptic.

Question 23.
Define the following by giving one example of each:

  1. Antiseptics
  2. Antioxidants
  3. Narcotic analgesics

Answer:

  1. Antiseptics are the chemicals applied to the living tissues either to kill or prevent the growth of micro organisms. Example : dettol.
  2. Antioxidants are the compounds which retards the action of oxygen on food and reduces its rate of decomposition by oxidation. Example: BHA.
  3. Narcotic analgesics are the chemicals used for the relief of pst operative pain. Example – morphine.

Question 24.
In order to wash clothes which cleaning agent what will you prefer and why: soap or synthetic detergents? Give one advantage of soaps and synthetic detergents each.
Answer:
Soaps have straight hydrocarbon chains and are easily degraded by bacteria present in the sewage water and hence, do not cause water pollution. Most of the detergents are non – biodegradable and hence cause water pollution of rivers and waterways. So, one will prefer soap.

Question 25.
Name the action of the following on the human body.

  1. Aspirin
  2. Penicillin
  3. Phenacetin
  4. Morphine
  5. Analgin
  6. Luminal
  7. Seconal
  8. Streptomycin

Answer:

  1. Aspirin is an analgesic which is used for relieving pain. It also prevents heart attack.
  2. Penicillin is an antibiotic used against large number of infections caused by various cocci, gram positive bacteria, etc. It is an effective drug for pneumonia, bronchitis, sore throat.
  3. Phenacetin is an antipyretic drug used to bring down the temperature of body in high fever.
  4. Morphine is an strong analgesic. It is a narcotic drug. It cause addiction. It gives relief from acute pain, induce sleep and unconsciousness in higher doses.
  5. Analgin is an antipyretic and analgesic. It brings down the temperature of body in fever and give relief from pain.
  6. Luminal produces sleep and it is a habit forming drug. It is also called a sedative tranquilliser.
  7. Seconal is an antidepressant (tranquiliser). Sometimes the patients are highly depressed and loses self – confidence. This drug produces feeling of well being and improved efficiency.
  8. Streptomycin is used as an antibiotic. It is used to cure tuberculosis.

Samacheer Kalvi 12th Chemistry Chemistry in Everyday Life 5 mark Questions

Question 1.
Explain free radical polymerisation with example.
Answer:
1. When alkenes are heated with free radical initiator such as benzoyl peroxide, they undergo polymerisation reaction. For example, styrene polymerises to polystrene when it is heated with a peroxide initator. The mechanism involves the following steps.

2. Initiation – Formation of free radical.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-59

3. Propagation step.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-60

4. Chain growth will continue with the successive addition of several thousands of monomer units.

5. Termination:
The above chain reaction can be stopped by stopping the supply of monomer or by coupling of two chains or reaction with an impurity such as oxygen.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-61

Question 2.
How are polymers classified on the basis of forces operating between their molecules? To which of these classes does nylon-6,6 belong?
Answer:

  1. Elastomers: The polymer chains are held together by weak intermolecular forces. Example – Buna – S, Buna – N, Neoprene.
  2. Fibres: They have strong forces of attraction. Example – Polymides, (Nylon 6,6), polyesters.
  3. Thermoplastics: They are long chain molecules capable of repeatedly softening on heating and hardening on cooling. Example – Polythene, polystyrene.
  4. Thermosetting plastics: They do not become soft on heating and cannot be remoulded. Example – Bakelite, Nylon – 6,6, belong to fibres.

Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-62

Common Errors

1. Medicines – Molecular fonnula are not given only structural fotmula are drawn.

Rectifications

1. It is written by counting the C, H, O, N in the compound. For example. Aspirin on Acetyt salicylic acid.
Samacheer Kalvi 12th Chemistry Solutions Chapter 15 Chemistry in Everyday Life-63

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Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds

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Tamilnadu Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds

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Samacheer Kalvi 12th Chemistry Chapter 13 Organic Nitrogen Compounds Text Book Evaluation

Samacheer Kalvi 12th Chemistry 13 Organic Nitrogen Compounds Multiple Choice Questions

Question 1.
Which of the following reagent can be used to convert nitrobenzene to aniline?
(a) Sn / HCl
(b) ZnHg / NaOH
(c) LiAIH4
(d) All of these
Answer:
(a) Sn / HCl

Question 2.
The method by which aniline cannot be prepared is ……………
(a) degradation of benzamide with Br2 / NaOH
(b) potassium salt of phthalimide treated with chlorobenzene followed by hydrolysis with aqueous NaOH solution.
(c) Hydrolysis of phenylcyanide with acidic solution
(d) reduction of nitrobenzene by Sn / HCI
Answer:
(b) potassium salt of phthalimide treated with chlorobenzene followed by hydrolysis with aqueous NaOH solution.

Question 3.
Which one of the following will not undergo Hofmann bromamide reaction?
(a) CH3CONHCH3
(b) CH3CH2CONH2
(c) CH3CONH2
(d) C6H5CONH2
Answer:
(a) CH3CONHCH3
Only primary amides undergo hoffmann bromamide reaction

Question 4.
Assertion : Acetamide on reaction with KOH and bromine gives acetic acid
Reason : Bromine catalyses hydrolysis of acetamide.
(a) if both assertion and reason are true and reason is the correct explanation of assertion,
(b) if both assertion and reason are true but reason is not the correct explanation of assertion.
(c) assertion is true but reason is false
(d) both assertion and reason are false
Answer:
(d) both assertion and reason are false

Question 5.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-1
(a) bromomethane
(b) a – bromo sodium acetate
(c) methanamine
(d) acetamide
Answer:
(c) methanamine
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-2

Question 6.
Which one of the following nitro compounds does not react with nitrous acid?
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-3
Answer:
(c) (CH3)3CNO2 – 30 nitroalkane

Question 7.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-4 this reaction is known as ………………
(a) Friedel – crafts reaction
(b) HVZ reaction
(c) Schotten – Baumann reaction
(d) none of these
Answer:
(c) Schotten – Baumann reaction

Question 8.
The product formed by the reaction an aldehyde with a primary amine
(a) carboxylic acid
(b) aromatic acid
(c) schiff ‘s base
(d) ketone
Answer:
(c) schiff ‘s base

Question 9.
Which of the following reaction is not correct.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-5
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-6
P – nitrosation takes places, the product is Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-7

Question 10.
When aniline reacts with acetic anhydride the product formed is …………….
(a) o – aminoacetophenone
(b) m – aminoacetophcnone
(c) p – aminoacetophenone
(d) acetanilide
Answer:
(d) acetanilide
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-8

Question 11.
The order of basic strength for methyl substituted amine solution is ………….
(a) N(CH3)3 > N(CH3)2H > N(CH3)H2 > NH3
(b) N(CH3)H2 > N(CH3)2H > N(CH3)3 > NH3
(c) NH3 > N(CH3)H2 > N(CH3)2H > N(CH3)3
(d) N(CH3)2H > N(CH3)H2 > N(CH3)3 > NH3
Answer:
(d) N(CH3)2H > N(CH3)H2 > N(CH3)3 > NH3

Question 12.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-9
(a) H3PO2 and H2O
(b) H+ / H2O
(c) HgSO4 / H2SO4
(d) Cu2Cl2
Answer:
(a) H3PO2 and H2O

Question 13.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-10
(a) C6H5 – OH
(b) C6H5 – CH2OH
(c) C6 H5 – CHO
(d) C6H5NH2
Answer:
(a) C6H5 – OH
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-11

Question 14.
Nitrobenzene on reaction with at 80 – 100°C forms which one of the following products?
(a) 1, 4 – dinitrobenzene
(b) 2, 4, 6 – tirnitrobenzene
(c) 1, 2 – dinitrobenzene
(d) 1, 3 – dinitrobenzene
Answer:
(d) 1, 3 – dinitrobenzene
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-12

Question 15.
C5H13N reacts with HNO2 to give an optically active compound – The compound is …………..
(a) pentan – 1 – amine
(b) pentan – 2 – amine
(c) N,N – dimethylpropan – 2 – amine
(d) N – methylbutan – 2 – amine
Answer:
(d) N – methylbutan – 2 – amine
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-13

Question 16.
Secondary nitro alkanes react with nitrous acid to form …………..
(a) red solution
(b) blue solution
(c) green solution
(d) yellow solution
Answer:
(b) blue solution

Question 17.
Which of the following amines does not undergo acetylation?
(a) t – butylamine
(b) ethylamine
(c) diethylamine
(d) triethylamine
Answer:
(d) triethyl amine (3°amine)

Question 18.
Which one of the following is most basic?
(a) 2, 4 – dichloroaniline
(b) 2, 4 – dimethyl aniline
(c) 2, 4 – dinitroaniline
(d) 2, 4 – dibromoaniline
Answer:
(b) 2, 4 – dimethyl aniline
CH3 is a +1 group, all other – I group. +1 group increase the electron density on NH2 and hence increases the basic nature.

Question 19.
When
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-14
is reduced with Sn / HCI the pair of compounds formed are ………..
(a) Ethanol, hydrozylamme hydrochloride
(b) Ethanol, ammonium hydroxide
(c) Ethanol, NH2OH
(d) C3H5NH2, H2O
Answer:
(a) Ethanol, hydrozylamine hydrochloride

Question 20.
TUPAC name for the amine
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-15 is ………………
(a) 3 – Bimethylamino – 3 – methyl pentane
(b) 3 (N,N – Triethyl) – 3 – amino pentane
(c) 3 – N, N – trimethyl pentanamine
(d) 3 – (N, N – Dimethyl amino) – 3 – methyl pentane
Answer:
(d) 3 – (N, N – Dimethyl amino) – 3 – methyl pentane

Question 21.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-16
Product ‘P’ in the above reaction is ………………
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-17
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-18

Question 22.
Ammonium salt of bcnzoic acid is heated strongly and the product so formed is reduced and then treated with NaNO2 / HCl at low temperature. The final compound formed is ……………
(a) Benzene diazonium chloride
(b) Benzyl alcohol
(c) Phenol
(d) Nitrosobenzene
Answer:
(b) Benzyl alcohol
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-19

Question 23.
Identify X in the sequence give below.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-20 + Methanoic acid
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-21
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-22

Question 24.
Among the following, the reaction that proceeds through an electrophilic substitution, is ……………..
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-23
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-24

Question 25.
The major product of the following reaction
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-25
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-26
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-27

Samacheer Kalvi 12th Chemistry 13 Organic Nitrogen Compounds Short Answer Questions

Question 1.
Write down the possible isomers of lthe C4H9NO2 give their IUPA names.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-28
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-29

Question 2.
There are two isomers with the formula CH3NO2. How will you distinguish between them?
Answer:
CH3NO2 has two isomers. They are
1. CH3 – NO2 (Nitromethane)
2.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-30

Question 3.
What happens when

  1. 2 – Nitropropane boiled with HCI
  2. Nitrobenezen electrolytic reduction in strongly acidic medium.
  3. Oxidation of tert – butylamine with KMnO4
  4. Oxidation of acetoneoxime with triuluoroperoxy acetic acid.

Answer:
1. 2 – Nitropropane boiled with HCI:
2 – nitropropane upon hydrolysis with boiling HCl give a ketone (2 – propanone) and nitrous oxide.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-31

2. Nitrobenezen electrolytic reduction in strongly acidic medium:
Electrolytic reduction of nitrobenzene in weakly acidic medium gives aniline but in strongly acidic medium, it gives p – aminophenol obviously through the acid – cataLysed rearrangement of the initially formed phenyihydroxylamine.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-32

3. Oxidation of tert – butylamine with XMnO4:
In general, primary amines, in which the – NH2 group is attached to a tertiary carbon can be oxidised with KMnO4 to the corresponding nitro compound in excellent yield. Therefore 3° – butylamine oxidised to give 2 – methyl – 2 – nitropropane.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-33

4. Oxidation ofacetoneoxime with trifluoroperoxy acetic acid:
Oxidation ofacetoneoxime with trifluoroperoxy acetic acid gives 2 – nitropropane.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-34

Question 4.
How will you convert nitrobenzene into

  1. 1, 3, 5 – trinitrobenzene
  2. o and p – nitrophenol
  3. m – nitro aniline
  4. azoxybenzene
  5. hydrozabenzene
  6. N – phenylhydroxylamine
  7. aniline

Answer:
1. Conversion of nitrobenzene into 1, 3, 5 – trinitrobenzene:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-35

2. Conversion of nitrobenzene into o and p – nitrophenol:
(a) Method I:
Nitrobenzene heated with solid KOH at 340 K gives a low yield of a mixture of 0 – and P – nitrophenols.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-36

(b) Method II:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-37

3. Conversion of nitrobenzene into m – nitro aniline:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-38

4. Conversion of nitrobenzene into azoxybenzene:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-39

5. Conversion of nitrobenzene into hydrazobenzene:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-40

6. Conversion of nitrobenzene into N – phenylhydrozylamine:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-41

7. Conversin of nitrobenzene into aniline:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-42

Question 5.
Identify compounds A,B and C in the following sequence of reactions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-43
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-44
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-45
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-46
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-47
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-48

Question 6.
Write short flotes on the following

  1. Hoffmann’s bromide reaction
  2. Ammonolysis
  3. Gabriel phthalimide synthesis
  4. Schotten – Baumann reaction
  5. Carbylamine reaction
  6. Mustard oil reaction
  7. Coupling reaction
  8. Diazotisation
  9. Gomberg reaction

Answer:
1. Hoffmann’s bromide reaction:
When Amides are treated with bromine in the presence of aqueous or ethanolic solution of KOH, primary amines with one carbon atom less than the parent amides are obtained.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-49

2. Ammonolysis:
When Alkyl halides (or) benzylhalides are heated with alcoholic ammonia in a sealed tube, mixtures of 1°, 2° and 3° amines and quaternary ammonium salts are obtained.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-50

3. Gabriel phthalimide synthesis:
Gabriel synthesis is used for the preparation of Aliphatic primary amines. Phthalimide on treatment with ethanolic KOH forms potassium salt of phthalimide which on heating with alkyl halide followed by alkaline hydrolysis gives primary amine.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-51

4. Schotten – Baumann reaction:
Aniline reacts with benzoylchloride (C6H5COCl) in the presence of NaOH to give N – phenyl benzamide. This reaction is known as Schotten Baumann reaction. The acylation and benzoylation are nucleophilic substitutions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-52

5. Carbylamine reaction:
Aliphatic (or) aromatic primary amines react with chloroform and alcoholic KOH to give isocyanides (carbylamines), which has an unpleasant smell. This reaction is known as carbylamines test. This test used to identify the primary amines.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-53

5. Mustard oil reaction:
When primary amines are treated with carbon disuiphide (CS2), N – alkyldithio carbonic acid is formed which on subsequent treatment with HgCI2, give an alkyl isothiocyanate.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-54

6. Coupling reaction:
Benzene diazonium chloride reacts with electron-rich aromatic compounds like phenol, aniline to form brightly coloured azo compounds. Coupling generally occurs at the para position. If para position is occupied then coupling occurs at the ortho position. Coupling tendency is enhanced if an electron-donating group is present at the para – position to Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-56 group. This is an electrophilic substitution.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-55

7. Diazotisation:
Aniline reacts with nitrous acid at low temperature (273 – 278 K) to give benzene diazonium chloride which is stable for a short time and slowly decompose seven at low temperatures. This reaction is known as diazotization.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-57

8. Gomberg reaction
Benzene diazonium chloride reacts with benzene in the presence of sodium hydroxide to give biphenyl. This reaction in known as the Gomberg reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-58

Question 7.
How will you distinguish between primary secondary and tertiary alphatic amines.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-59

Question 8.
Account for the following

  1. Aniline does not undergo Friedel – Crafts reaction
  2. Diazonium salts of aromatic amines are more stable than those of aliphatic amines
  3. pkb of aniline is more than that of methy lamine
  4. Gabriel phthalimide synthesis is preferred for synthesising primary amines.
  5. Ethylamine is soluble in water whereas aniline is not
  6. Amines are more basic than amides
  7. Although amino group is o – and p – directing in aromatic electrophilic substitution reactions, aniline on nitration gives a substantial amount of m – nitroaniline.

Answer:
1. Aniline does not undergo Friedel – Crafts reaction:
Aniline being a Lewis base reacts with Lewis acid AiCl3 to form a salt.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-60
Due to the presence of a positive charge on N – atom in the salt the group Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-61 acts as a strongly deactivating group. As a result, it reduces the electron density in the benzene ring and which inhibits the electrophilic substitution reaction. Therefore aniline does not under go Friedel – Crafts reaction.

2. Diazonium salts of aromatic amines are more stable than those of aliphatic amines:
The diazonium salts of aromatic amines are more stable than those of aliphatic amines due to dispersal of the positive charge on the benzene ring as shown below.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-62

3. pKb of aniline is more than that of methylamine:
In aniline, the lone pair of electrons on the N – atom is delocalized over the benzene ring. As a result electron density on the nitrogen decreases. In contrast in CH3NH2, +I effect of CH3 increases the electron density on the N-atom. Therefore, aniline is a weaker base than methylamine and hence its pK value is more than that of methyl amine.

4. Gabriel phthalimide synthesis is preferred for synthesising primary amines:
Gabriel phthalimide reaction gives pure 10 amine without any contamination of 2° and 3°-amines. Therefore it is preferred for synthesising primary amines.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-63

5. Ethylamine is soluble in water whereas aniline is not:
Ethylamine when added to water forms intermolecular H – bonds with water. And therefore it is soluble in water. But aniline does not form H – bond with water to a very large extent due to the presence of a large hydrophobic – C6H5 group. Hence, aniline is insoluble in water.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-64

6. Amines are more basic than amides:
In simple amines, the lone pair of electrons is on nitrogen and hence available for protonation. In amides on the other hand, the electron pair on nitrogen is delocalised to the carboxyl oxygen through resonance and thus it is not available for protonation. So amines are more basic than amides.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-65

7. Although amino group is o – and p – directing in aromatic electrophilic substitution reactions, aniline on nitration gives a substantial amount of m – nitroaniline:
Nitration is usually carried out with a mixture of conc HNO3 and conc H2SO4. In the presence of these acids, most of aniline gets protonated to form anilinium ion. Therefore, in the presence of acids, the reaction mixture consists of aniline and anilinium ion.

Now – NH2, group in aniline is O, P – directing and activating while the – NH3 group is anilinium ion is meta – directing and deactivating. Whereas nitration of aniline (due to steric hindrance at o – position) mainly gives p-nitroaniline, the nitration of anilinium ion gives m – nitro aniline. In actual practice, approximately a 1 : 1 mixture of P and m – nitroaniline is formed.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-66

Question 9.
Arrange the following

  1. In increasing order of solubility in water, C6H5NH2, (C2H5)2NH , C2H5NH2
  2. In increasing order of basic strength
    • aniline, p – toludine and p – nitroaniline
    • C6H5NH2, C6H5NHCH3, C6H5NH2, p – Cl – C6H4 – NH2
  3. In decreasing order of basic strength in gas phase.
    C2H5NH2, (C2H5)3NH , (C2H5)3N and NH3
  4. In Increasing order of boiling point
    C2H5OH , (CH3)2NH, C2H5NH2
  5. In decreasing order of the pKb values
    C2H5NH2, C6H5NHCH3, (C2H)2NH4 and CH3NH2
  6. Increasing order of basic strength C6H5NH2, C6H5N(CH3)2, (C6H5)2NH and CH3NH2
  7. In decreasing order of basic strength
    Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-67

Answer:
1. Solubility decreases with increase in molecular mass of amines due to increase in the size of a hydrophobic hydrocarbon part and with decrease in the number of H – atoms on the N – atom which undergo H – bonding.

Now among the given compounds C6H5NH2 has the highest molecular mass of 93 followed by (C2H5)2NH with molecular mass of 73 with C2H5NH2 has the lowest molecular mass of 45. Thus the solubility increases in the order in which molecular mass decreases.

2. (a) The electron – donating groups increases the basic strength of amines while the electron – withdrawing groups decrease the basic strength of amines. Therefore p – nitroaniline is the weakest base followed by aniline while p – toluidine, which has methyl group and therefore it is the strongest base. Basic strength increases in the order. P – nitro aniline < aniline < p – toluidine

(b) Chlorine atom has both – I effect and + R effect since – I effect out weights the + R effect, therefore p – chloro aniline is weak base than aniline. Aikyl groups are electron – donating groups. ”

As a result the electron density on the nitrogen atom increases in the ethylamine and thus they can donate lone pair of electrons niore easily. Therefore Ethylamine is more base than aromatic amines.

Due to delocalization of lone pair of electrons of the N – atom over the benzene ring, C6H5NH, and C6H5NHCH3 are far less basic than C2H5NH2. Further due to +1 effect of the CH3 group, C6H5NHCH3 is little more basic than C6H5NH2. Therefore increasing order basic strength is

3. In the gas phase, solvent effects i.e., stabilization of the conjugate acids due to H – bonding, are absent. Therefore, in the gas phase, basic strength mainly depends upon the +1 effect of the alkyl groups. Since the +1 effect increases with the number of ailcyl groups,

therefore the basic strength of the amines decreases as the number of ethyl groups decreases from three in (C2H5)3N to two in (C2H5)2NH to one in C2H5NH2 and zero in NH3. Basic strength in the gas phase decreases in the order is,
(C2H5)3N > (C2H5)2N > C2H5NH2 > NH3

4. Since the electro negativity of O is higher than that of N, therefore, alcohols form stronger H – 0bonds than amines. In other words, the boiling points of alcohols are higher than those of amines of comparable molecular masses. Therefore the boiling point of C2H5OH (46) is higher than those of (CH3)2NH (45) and C2H5NH2 (45).

Further since the extent of H – bonding depends upon the number of H-atoms on the N-atom. Therefore 1° – amines with two H – atoms on the N – atom have higher boiling points than 2° – amines having only one H – atom. Therefore the boiling point of C2H5NH2 is higher than that of(CH3)2NH. Increasing order of boiling point is,
(CH3)2NH < C2H5NH < CH5OH

5. Due to delocalization of lone pair of electrons of the N – atom over the benzene ring, C6H5NHCH3 is far less basic than C2H5NH2, (C6H5)2NH and CH3NH2. Among C2H5NH2 and (C2H5), NH, (C2H5)2NH is more basic than C2H5NH2 due to greater +1 effect of the two C2H5 groups and stabilization of its conjugate acid by H – bonding.

Compare to Ethyl and methyl group, C2H5 – group has more +1 effect than CH3 – group. Therefore methylamine is weak base than ethylamine. Combining all these facts the relative basic strength of these four amines decreases in the order.

(C2H5)2NH > C2H5NH2 > CH3NH2 > C6H5NHCH3. Since a stronger base has a lower pKb value therefore, pKb values decrease in the reverse order. C6H5NHCH3 > CH3NH2 > C2H5NH2 > (C2H5)2NH

6. Due to delocalization of lone pair of electrons of the N-atom over the benzene ring, all aromatic amines are less basic than alkylamines i.e., CH3NH2. Presence of electron – donating groups ( – CH3) on the N – atom increases the basicity of substituted aniline with respect to C6H5NH2.

In (C6H5)2NH, the lone pair of electrons on the N – atom is delocalized over two benzene rings instead of one in C6H5NH2, therefore (C6H5)2NH is much less basic than C6H5NH2. Combining all the three trends together, the basic strength of the four amines increasing in the order.
(C6H5)2NH < C6H5NH2 < C6H5N (CH3)2 < CH3NH,

7. Aliphatic amines are more basic than aromatic amines. Therefore CH3CH2NH2 and CH3NH2 are more basic. Among the ethylamine and methylamine. ethylamine was experienced more +1 effect than methylamine and hence ethylamine is more basic than methylamine.

Nitrogroup has a powerful electron withdrawing group and they have both – R effect as well as – I effect. As a result, all the nitro anilines are weaker bases than aniline. In P – nitroaniline
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-68
both – R effect and – I effect of the NO2 group decrease the basicity. Therefore decreasing order of basic strength is,
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-69
Ethylamine > Methylamine > Aniline > p – nitro aniline

Question 10.
How will you prepare propan – 1 – amine from

  1. butane nitrile
  2. propanamide
  3. 1 – nitropropane

Answer:
1. Preparation of propan -1- amine from butane nitrile.
Butane nitrile treated with acid hydrolysis followed by Hoffmann’s bromamide degradation. gives propan – 1 – amine.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-70

2. Preparation of propan – 1 – amine from propanamide.
When propanamide is treated with LiAIH4 in the presence of water gives propan – 1 – amine.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-71

3. Preparation of propan – 1 – amine from 1 – nitropropane.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-72
Reduction of 1 – Nitropropane using H2 / Ni or Fe / HCl gives propan – 1 – amine.

Question 11.
Identify A,B,C and D
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-73
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-74

Question 12.
How will you convert dlethylamine into

  1. N, N – dlethylacetamide
  2. N – nitrosodiethylamine

Answer:
1. Conversion of diethylamine into N, N – diethylacetamide.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-75
Diethylamine react with acetyichioride in the presence of pyridine to form N, N – diethyl acetamide.

2. Conversion of diethylamine into N – nitrosodiethylamine.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-76

Question 13.
Identify A,B and C
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-77
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-78

Question 14.
Identify A, B, C and D
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-79
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-80

Question 15.
Complete the following reaction
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-81
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-82

Question 16.
Predict A, B, C and D for the follwing reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-83
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-84

Question 17.
A dibromo derivative (A) on treatment with KCN followed by acid hydrolysis and heating gives a monobasic acid (B) along with liberation of CO2. (B) on heating with liquid ammonia followed by treating with Br2 / KOH gives (C) which on treating with NaNO2 and HCI at low temperature followed by oxidation gives a monobasic acid (D) having molecular mass 74. Identify A to D.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-85

Question 18.
Identify A to E in the following frequncy of reactions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-86
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-87

Samacheer Kalvi 12th Chemistry 13 Organic Nitrogen Compounds Evaluate Yourself

Question 1.
Write all possible isomers for the following compounds.

  1. C2H5 – NO2
  2. C3H7 – NO2

Answer:
1. Possible isomers for C2H5NO2 as following

(a) CH3 – CH2 – NO2 – Nitroethane

(b) CH3 – CH2 – O – N = O – Ethyl nitrite

(c)Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-88

(d) H2N – CH2 – COOH – Glycine (amino acid)

(e) Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-89

(f) Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-90

(g) Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-91

2. Possible isomers for C3H7NO2 as follows.

(a) CH3 – CH2 – CH2 – NO2 – 1 – Nitropropane

(b) CH3 – CH2 – CH2 – O – N = O – propane – 1 – nitrite

(c) Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-92

(d) Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-93

(e) Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-94

(f) H2N – CH2 – CH2 – COOH – Alanine

Question 2.
Find out the product of the following reactions
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-95
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-96

Question 3.
Predict the major product that would be obtained on nitration of the following compounds.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-97
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-98

Question 4.
Draw the structure of the following compounds

  1. Neopentylamine
  2. Tert – butylamine
  3. α – amino propionaldehyde
  4. tribenzylamine
  5. N – ethyl – N – methylhexan – 3 – amine

Answer:
1. Neopentylamine:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-99

2. Tert – butylamine
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-100

3. α – amino propionaldehyde
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-101

4. tribenzylamine
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-102

5. N – ethyl – N – methylhexan – 3 – amine
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-103

Question 5.
Give the correct IUPAC names for the following amines.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-104
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-105

Samacheer Kalvi 12th Chemistry 13 Organic Nitrogen Compounds Additional Question

Samacheer Kalvi 12th Chemistry 13 Organic Nitrogen Compounds 1 Mark Questions and Answers

I. Choose the correct answer.

Quesiton 1.
Which one of the following play an important role in bioregulation and neurotransmission?
(a) Acid derivatives
(b) Carbonyl compounds
(c) Organic derivatives of ammonia
(d) Aromatic hydro carbons
Answer:
(c) Organic derivatives of ammonia

Question 2.
Which of the following is needed to maintain the health of nerves, skin and red blood cells?
(a) Vitamin B12
(b) Vitamin B6
(c) Vitamin B1
(d) Vitamin C
Answer:
(b) Vitamin B6

Question 3.
Which one of the following is needed to maintain the health of nerves and skin?
(a) Pyridoxine
(b) Cobalamine
(c) Dopamine
(d) Histamine
Answer:
(a) Pyridoxine

Question 4.
Which one of the following is act as neurotransmitter?
(a) Pyridoxine
(b) Histamine
(c) Dopamine
(d) Cyano cobalamine
Answer:
(c) Dopamine

Question 5.
Which one of the following dilates blood vessels?
(a) Histamine
(b) Streptomycin
(c) Penicillin
(d) Dopamine
Answer:
(a) Histamine

Question 6.
Which one of the following is an example of primary nitro alkane?
(a) 2 – nitropropane
(b) Ethyl nitrite
(c) Nitro ethane
(d) 2 – methyl – 2 – nitropropane
Answer:
(c) Nitro ethane

Question 7.
2 – methyl – 2 – nitropropane belongs to
(a) 1° nitro alkane
(b) 3° nitro alkane
(c) 2° nitro alkane
(d) nitro arenes
Answer:
(b) 3° nitro alkane

Question 8.
Which of the following is an example for 2° nitro alkane?
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-199
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-199

Question 9.
Which one of the following is an example for nitro arenes?
(a) C6H5 – CH2 NO6
(b) C6H5NH2
(c) CH3 – CH2 – O – NO
(d) C6H5NO2
Answer:
(d) C6H5NO2

Question 10.
The IUPAC name of
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-200 is ………………
(a) 1 – nitro butane
(b) 2 – methyl – 1 – nitro propane
(c) Isobutyl nitrate
(d) 1 – Nitro iso butane
Answer:
(b) 2 – methyl – 1 – nitro propane

Question 11.
Which one of the following is the structure of 2, 2 – dimethyl – 1 – nitro propane?
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-201
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-202

Question 12.
1 – nitrobutane and 2 – methyl – 1 – mtropropane are belong to ……………..
(a) position isomerism
(b) functional isomerism
(c) Tautomerism
(d) chain isomerism
Answer:
(d) chain isomerism

Question 13.
Which of the following pair shows functional isomerism?
(a) 1 – nitro butane and 2 – nitro butane
(b) 1 – nitro butane and butyl nitrite
(c) 1 – nitro butane and 2 – methyl – 1 – nitropropane
(d) 2 – nitro butane and 2 – methyl – 2 – nitro propane
Answer:
(b) 1 – nitro butane and butyl nitrite

Question 14.
Which of the following pair shows position isomerism?
(a) 1 – nitro butane and butyl nitrite
(b) Nitro methane and methyl nitrite
(c) 1 – nitro butane and 2 – nitro butane
(d) 1 – nitro butane and 2 – methyl – 1 – nitro propane
Answer:
(c) 1 – nitro butane and 2 – nitro butane

Question 15.
Nitro methane and methyl nitrite are the examples of ……………
(a) Position isomerism
(b) chain isomerism
(c) metarnersm
(d) Tautomerism
Answer:
(d) Tautomerism

Question 16.
Consider the following statements.
(i) Nitro form of alkane dissolves in NaOH instantly
(ii) Nitro form of alkane decolourises FeCI3 solution
(iii) Nitro form of alkane are more acidic
Which of the above statement(s) is / are not correct?
(a) (i) only
(b) (ii) and (iii)
(c) (i) and (iii)
(d) (ii) only
Answer:
(c) (i) and (iii)

Question 17.
Consider the following statements.
(i) Aci form of nitro alkanes dissolves in NaOH slowly.
(ii) Aci form of nitro alkane gives reddish brown colour with FeCl3
(iii) Aci form of nitro alkane’s electrical conductivity is low.
Which of the above statement(s) is / are correct?
(a) (ii) only
(b) (i) only
(c) (iii) only
(d) (i) and (iii)
Answer:
(a) (ii) only

Question 18.
Which one of the following does not exhibit tautomerism?
(a) 1 – nitro ethane
(b) Nitro methane
(c) methyl nitrite
(d) 2 – methyl – 2 – nitro propane
Answer:
(d) 2 – methyl – 2 – nitro propane

Question 19.
Identify the compound which does not exhibit tautomerism?
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-203
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-204

Question 20.
The correct decreasing order of acidity of nitro alkane is …………….
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-205
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-206

Question 21.
Which one of the following mechanism is followed by the reaction of Ethyl bromide with ethanolic solution of potassium nitrite ……………
(a) SN1
(b) SN2
(c) SNi
(d) E1
Answer:
(b) SN2

Question 22.
Which one of the following is formed when Ethyl bromide reacts with ethanolic solution of potassium nitrite?
(a) Nitro methane
(b) 2 – Nitro propane
(c) 1 – nitro propane
(d) nitro ethane
Answer:
(d) nitro ethane

Question 23.
Which method is used to separate the mixture of nitroalkane?
(a) Crystallization
(b) zone refining
(c) fractional distillation
(d) sublimation
Answer:
(c) fractional distillation

Question 24.
Which of the following is formed when ethane is heated with conc. HNO3 at 675 K?
(a) Nitro propane
(b) Nitro ethane
(c) Nitro methane
(d) both (ii) and (iii)
Answer:
(d) both (ii) and (iii)

Question 25.
What is the product formed when α – chioro acetic acid is boiled with aqueous solution of sodium nitrite?
(a) Nitro ethane
(b) Nitromethane
(c) Acetamide
(d) α – chloro acetamide
Answer:
(b) Nitromethane

Question 26.
Which one of the following reagent is used to convert teritary butylamine to tertiary nitro alkane?
(a) Aqueous KMnO4
(b) Cone HNO3
(c) Sn / HCI
(d) alcoholic KOH
Answer:
(a) Aqueous KMnO4

Question 27.
The reagent used in the conversion of acetaldoxime to nitro ethane (1°) is …………
(a) aqueous KMnO4
(b) trifluoro peroxy acetic acid
(c) alcoholic KOH
(d) Cone. HNO3
Answer:
(b) trifluoro peroxy acetic acid

Question 28.
Which of the following is called oil of mirbane?
(a) Nitro methane
(b) Nitro propane
(c) Nitro benzene
(d) Nitro ethane
Answer:
(c) Nitro benzene

Question 29.
On direct nitration of nitro benzene gives ………………
(a) 0 – dinitro benzene
(b) m – dinitro benzene
(c) p – dinitro benzene
(d) 2, 4, 6 – trinitrobenzene
Answer:
(b) m – dinitro benzene

Question 30.
Amino group can be directly converted into nitro group by ……………
(a) Caro’s acid
(b) Fuming mixture of conc. HNO3 + conc. H2SO4
(c) NaNO2 + HCI
(d) Ethanolic KNO2
Answer:
(a) Caro’s acid

Question 31.
Amino group can be directly converted into nitro group by ………….
(a) Caro’s acid
(b) marshall’s acid
(c) Peroxy trifluoro acetic acid
(d) all the above
Answer:
(d) all the above

Question 32.
Consider the following statements.
(i) Nitro alkanes have high points because of their highly polar nature
(ii) Alkyl nitrites have lower boiling points than nitro alkanes.
(iii) Nitro alkanes are readily soluble in water due to intermolecular hydrogen bonding formation.
Which of the above statement(s) is / are not correct?
(a) (i) only
(b) (ii) only
(c) (iii) only
(d) (i) and (ii)
Answer:
(c) (iii) only

Question 33.
The reagent used to convert Nitromethane to methyl amine is ……..
(a) Zn/NH4Cl
(b) Sn/HCI
(c) H2SO5
(d) H2S2O8
Answer:
(b) Sn/HCI

Question 34.
The reagent used to convert Nitromethane to N – methyl hydroxylamine is …………
(a) Sn/HCl
(b) Zn/NH4CI
(c) Ni
(d) Pd/BaSO4
Answer:
(b) Zn/NH4CI

Question 35.
Which one of the following is formed when ethyl nitrite is treated with Sn/HCl?
(a) Nitro ethane
(b) Ethylamine
(c) Ethyl alcohol
(d) Ethanamide
Answer:
(c) Ethyl alcohol

Question 36.
The product formed when nitro ehtane is boiled with conc. HCl is ……………
(a) Acetic acid
(b) Ethyl chloride
(c) Ethanoyl chloride
(d) Amino ehtane
Answer:
(a) Acetic acid

Question 37.
Which one of the following is formed when 2- nitro propane is boiled with conc.HCI?
(a) Ethanoic acid
(b) Propanoic acid
(c) Propanoyl chloride
(d) Acetone
Answer:
(d) Acetone

Question 38.
Which of the following does not react with conc. HCI?
(a) Nitro ethane
(b) 2 – methyl – 2 – nitropropane
(c) 2 – nitro propane
(d) Aniline
Answer:
(b) 2 – methyl – 2 – nitropropane

Question 39.
Acid (or) Basic hydrolysis of ethyl nitrite gives ………….
(a) Ethanoic acid
(b) Nitro ethane
(c) Ethanol
(d) Aceto nitrile
Answer:
(c) Ethanol

Question 40.
Which one of the following is formed when nitro methane reacts with chlorine and NaOH?
(a) CH3CI
(b) CH3COCl
(c) CCI3NO2
(d) CHCI2NO2
Answer:
(c) CCI3NO2

Question 41.
Which one of the following reagent is used to convert Nitrobenzene to aniline?
(a) Sn/HCI
(b) Zn/NH4CI
(c) Fe/H2O(g)
(d) Zn/NaOH
Answer:
(a) Sn/HCI

Question 42.
Which one of the following is the best reagent used to convert Nitrobenzene into Nitroso benzene?
(a) Sn/HCI
(b) Zn/NH4CI
(c) Fe/H2O(g)
(d) SnCl2 + KOH
Answer:
(c) Fe/H2O(g)

Question 43.
Identify the reagent used to convert Nitrobenzene into hydrazo benzene?
(a) Zn/NaOH
(b) Zn/NH4CI
(c) Sn/HCI
(d) SnCI2 + KOH
Answer:
(a) Zn/NaOH

Question 44.
Which one of the following is formed when nitrobenzene is treated with Fe/H2O(Steam)?
(a) Aniline
(b) Phenyl hydroxylamine
(c) Nitroso benzene
(d) Azobenzene
Answer:
(c) Nitroso benzene

Question 45.
Which one of the following is formed when nitrobenzene is treated with Zn/NaOH?
(a) Phenyl amine
(b) Phenyl hydroxylamine
(c) Azo benzene
(d) Hydrazo benzene
Answer:
(d) Hydrazo benzene

Question 46.
Which one of the following is formed when nitrobenzene is treated with SnCI2/KOH?
(a) Azo benzene
(b) Azoxy benzene
(c) Hydrazo benzene
(d) Nitroso benzene
Answer:
(a) Azo benzene

Question 47.
Which of the following is formed when nitro benzene undergoes electrolytic reduction?
(a) Aniline
(b) Phenyl hydroxylamine
(c) p – amino phenol
(d) all the above
Answer:
(d) all the above

Question 48.
Which of the following can be used to reduce nitrobenzene to aniline?
(a) LiAIH4
(b) Sn + HCI
(c) Pt/H2
(d) all the above
Answer:
(d) all the above

Question 49.
What will be the product formed when nitrobenzene is treated with conc. HNO3 and conc.H2SO4 at 373K?
(a) 1, 3 – dinitro benzene
(b) 1, 4 – dinitro benzene
(c) 1, 3, 5 – trinitro benzene
(d) all the above
Answer:
(a) 1, 3 – dinitro benzene

Question 50.
Which one of the following is formed when nitrobenzene is treated with cone. HNO3 and H2SO4 473 K?
(a) 1, 2 – din itro benzene
(b) 1, 4 – dintro benzene
(c) 1, 3 – dinitro benzene
(d) 1, 3, 5 – trinitro benzene
Answer:
(d) 1, 3, 5 – trinitro benzene

Question 51.
What will be the product formed when 1, 3, 5 – trinito toluene is treated with acidified Na2Cr2O7 and sodalime?
(a) TNB
(b) TNT
(c) TNG
(d) GTN
Answer:
(a) TNB

Question 52.
What is the IUPAC name of
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-207
(a) Tertiary butyl amine
(b) Trimethyl amine
(c) N, N – dimethyl methanamine
(d) N – methyl ethanamine
Answer:
(c) N, N – dimethyl methanamine

Question 53.
Which one of the following is called (N – ethyl – N – methyl) propanamine?
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-208
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-209

Question 54.
The IUPAC name of
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-210 is ……………..
(a) Methyl iso propyl amine
(b) N – methyl propan – 1 – amine
(c) N, N – dimethyl methanamine
(d) propan – 1 – amine
Answer:
(b) N – methyl propan – 1 – amine

Question 55.
What is the IUPAC name of
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-211
(a) Ethyl methyl isopropylamine
(b) N, N – dimethyl methanamine
(c) N, N – diethyl butan – 1 – amine
(d) N – ethyl – N – methyl propan -2 – amine
Answer:
(d) N – ethyl – N – methyl propan -2 – amine

Question 56.
Which one of the following is called Hexane – 1, 6 – diamine?
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-212
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-213

Question 57.
Which one of the following is the TUPAC name of CH2 = CH – CH2 – NH2?
(a) Isopropyl amine
(b) Allylamine
(c) 1 – amino propane
(d) prop – 2 – en – 1 – amine
Answer:
(d) prop – 2 – en – 1 – amine

Question 58.
Which one of the following is the structure of phenyl methanamine?
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-214
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-215

Question 59.
Consider the following statements.
(i) Nitrogen atom of amines is trivalent and carries a lone pair of electron.
(ii) Nitrogen atom of amines is Sp2 hybridised.
(iii) Amines posses pyramidal geometry.
Which of the above statement(s) is / are correct?
(a) (i) and (ii)
(b) (i) and (iii)
(c) (iii) only
(d) (ii) only
Answer:
(b) (i) and (iii)

Question 60.
What is the C – N – C bond angle of trimethylamine?
(a) 109°. 5′
(b) 107°
(c) 108°
(d) 108°. 31’
Answer:
(c) 108°

Question 61.
Which one of the following is the geometry of amines?
(a) Tetrahedral
(b) Pyramidal
(c) Planar triangle
(d) square planar
Answer:
(b) Pyramidal

Question 62.
Which one of the following is formed when cyano methane reacts with LiAIH4?
(a) Ethanamine
(b) Methane
(c) Methanoic acid
(d) Acetic acid
Answer:
(a) Ethanamine

Question 63.
The reducing agent used in mendius reaction is …………
(a) H2/Ni
(b) LiAIH4
(c) Na/C2H5OH
(d) Sn/HCI
Answer:
(c) Na/C2H5OH

Question 64.
The product formed when methyl isocyanide is reduced by Na(Hg)/C2H5OH is …………
(a) Isopropyl amine
(b) Ethanamine
(c) N – methyl methanamine
(d) N – ethyl methanamine
Answer:
(c) N – methyl methanamine

Question 65.
Which one of the following is formed when acetamide reacts with LiAlH4 and H2O?
(a) Methyl amine
(b) Ethylamine
(c) Ammonium acetate
(d) N – methyl ethanamine
Answer:
(b) Ethylamine

Question 66.
In which reaction acetamide is changed to methylamine by the action of Br2/KOH?
(a) Gapriel phthalimide synthesis
(b) Hoffmann degration reaction
(c) Mendius reaction
(d) Mustard oil reaction
Answer:
(b) Hoffmann degration reaction

Question 67.
Which one of the reaction is used in the synthesis of aliphatic primary amines?
(a) Hoffmann ammonolysis
(b) Rosenmund’s reduction
(c) Carbylamine reaction
(d) Gabriel phthalimide synthesis
Answer:
(d) Gabriel phthalimide synthesis

Question 68.
The conversion of ethanol into all types of amines by the action of ammonia along with Alumina is …………
(a) HVZ reaction
(b) Sabatier – mailhe method
(c) Carbylamine reaction
(d) Mendius reaction
Answer:
(b) Sabatier – mailhe method

Question 69.
Consider the following statements.
(i) Amines have higher boiling point than alcohols.
(ii) Lower aliphatic amines are colourless gases whereas higher amines have fish like small.
(iii) Aniline and arylamines are colourless but when exposed to air they become coloured due to oxidation.
Which of the above statement(s) is / are correct?
(a) (i) and (ii)
(b) (ii) and (iii)
(c) (i) only
(d) (iii) only
Answer:
(b) (ii) and (iii)

Question 70.
The correct order of basic strength in the case of ailcyl substituted amines is …………
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-217
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-216

Question 71.
The correct order of basic strength in the case of substituted ethyl amines is ………….
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-218
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-219

Question 72.
The relative basicity of amine follows the order as ………….
(a) Alkyl amines > Aralkyl amines > Ammonia > N – aralkylamine > Arylamine
(b) Aralkyl amines > Ammonia > Arylamine > Alkyl amine > N – aralkylamine
(c) Arylamine Alkyl amine N – aralkylanilne
(d) N – aralkylamine < Arylamine < Ammonia < Alkyl amine < Aralkyl amine Answer: (a) Alkyl amines > Aralkyl amines > Ammonia > N – aralkylamine > Arylamine
Answer:
(a) Alkyl amines > Aralkyl amines > Ammonia > N – aralkylamine > Arylamine

Question 73.
Identify the name of the reaction in which aniline reacts with Benzoyl chloride to form N – Phenyl benzamide?
(a) Hoffmann degradation reaction
(b) Gabriel phthalimide synthesis
(c) Schotten – Baumann reaction
(d) Mustard oil reaction
Answer:
(c) Schotten – Baumann reaction

Question 74.
Which one of the product is formed when aniline reacts with benzoyl chloride in the presence of NaOH?
(a) N – Phenyl benzamide
(b) N – Phenyl ethanamide
(c) Benzamide
(d) N – Benzyl aniline
Answer:
(b) N – Phenyl ethanamide

Question 75.
Which one of the following is formed as product when ethylamine reacts with nitrous acid?
(a) Ethyl nitrite
(b) Nitro ethane
(c) Ethanol
(d) Ethane nitrile
Answer:
(c) Ethanol

Question 76.
Identify X in the following reaction?
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-220
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-221
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-222

Question 77.
The reaction of aniline with nitrous acid at low temperature is known as …………
(a) Carbylamme reaction
(b) mustard oil reaction
(c) Diazotisation
(d) Sand meyer’s reaction
Answer:
(c) Diazotisation

Question 78.
Which one of the product is formed with N-methyl aniline reacts with nitrous acid?
(a) Anilinium chloride
(b) N – nitroso methyl phenylamine
(c) Benzene diazonium chloride
(d) Benzylamine
Answer:
(b) N – nitroso methyl phenylamine

Question 79.
Which one of the réaction is called Libermann’s nitroso set?
(a) N – methyl aniline Conc. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-223 N – nitroso methyl phenylamine.
(b) Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-224 Benzene diazonium chloride.
(c) Aniline + CHCI3 + 3KOH → Phenyl iso cyanide.
(d) Methyl amine + CHCl3 + 3KOH → Methyl iso cyanide.
Answer:
(a) N – methyl aniline Conc. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-223 N – nitroso methyl phenylamine.

Question 80.
The conversion of N – methyl aniline into N – nitrosomethyl phenyl amine is known as …………
(a) Carbylamine reaction
(b) mustard oil reaction
(c) Diazotisation
(d) Libermann’s nitroso test
Answer:
(d) Libermann’s nitroso test

Question 81.
Which one of the following reaction is used to identify primary amines?
(a) Schotten – Baumann reaction
(b) Carbylamine reaction
(c) Sand meyer’s reaction
(d) Gattermann reaction
Answer:
(b) Carbylamine reaction

Question 82.
The reaction between methylamine and CS2 is known as ……………
(a) mustard oil reaction
(b) Carbylamine reaction
(c) Sand meyer’s reaction
(d) Gabriel phthalirnide synthesis
Answer:
(a) mustard oil reaction

Question 83.
Which one of the following is formed when aniline reacts with CS2 followed by hydrolysis by cone. HCI?
(a) Phenyl isocyanide
(b) phenyl cyanide
(c) Phenvi isothio cyanate
(d) Benzene diazonium chloride
Answer:
(c) Phenvi isothio cyanate

Question 84.
Consider the following reaction.
(i) Aniline does not undergo friedel – crafts reaction
(ii) Aromatic amine on treatment with NaNO2 + HCI gives diazonium slats.
(iii) Aniline is more basic than ammonia.
Which of the above statement(s) is / are not correct?
(a) (i) only
(b) (i) and (ii)
(c) (iii) only
(d) (ii) only
Answer:
(c) (iii) only

Question 85.
Which one of the following is formed when aniline reacts with cone. H2SO4?
(a) Zwitter ion
(b) Acetanilide
(c) Suiphanilic acid
(d) p – sulphonic bcnzoic acid
Answer:
(c) Suiphanilic acid

Question 86.
Consider the following statements.
(i) Benzene diazonium chloride aqueous solution are neutral to litmus.
(ii) The stability of arene diazonium salt is due to the dispersal of the positive charge over the ring.
(iii) Benzenediazonium chloride is reddish brown colour liquid.
Which of the above statement(s) is / are correct?
(a) (iii) and (ii)
(b) (i) and (ii)
(c) (i) and (iii)
(d) (iii) only
Answer:
(b) (i) and (ii)

Question 87.
Identify the product formed when Benzene diazonium chloride reacts with phosphinic acid?
(a) Benzene
(b) Chioro benzene
(c) Phenol
(d) cyano benzene
Answer:
(a) Benzene

Question 88.
The conversion of Benzene diazonium chloride into chlorobenzene is known as …………
(a) Gabriel phthalimide synthesis
(b) Carbylamine reaction
(c) Sand meyer reaction
(d) Coupling reaction
Answer:
(c) Sand meyer reaction

Question 89.
Identify X and Y in the following reaction
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-225
(a) C6H5CI + N2
(b) C6H6 + N2
(c) C6H5CI + NH4CI
(d) C6H5CI + H2
Answer:
(a) C6H5CI + N2

Question 90.
Which one of the following is formed when benzene diazonium chloride is boiled with water?
(a) Benzene
(b) Phenol
(c) Chiorobenzene
(d) Aniline
Answer:
(b) Phenol

Question 91.
Complete the following reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-226
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-1.1
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-106

Question 92.
What is the name of the reaction in which benzene diazonium chloride react with benzene to give Biphenyl?
(a) Sandmeyer’s reaction
(b) Gomberg reaction
(c) Gattermann reaction
(d) Baltz – schiemann reaction
Answer:
(b) Gomberg reaction

Question 93.
Which one of the following reagent reacts with ben.zene diazonium chloride to give biphenyl?
(a) Chioro benzene
(b) Bromobenzene
(c) Benzene
(d) Acetic acid
Answer:
(c) Benzene

Question 94.
Which one of the following is formed when Benzene dia.zonium chloride reacts with Aniline?
(a) p – hydroxy azo benzene
(b) 2 – phenyl azo – 4 – methyl
(c) Biphenyl
(d) p – amino azo benzene
Answer:
(d) p – amino azo benzene

Question 95.
Which one of the following should react with Benzene diazonium chloride to get orange dye?
(a) Aniline
(b) phenol
(c) 0 – cresol
(d) P – cresol
Answer:
(b) phenol

Question 96.
Aniline + Benzene diazonium chloride → X. Identify X.
(a) orange dye
(b) yellow dye
(c) malachite green dye
(d) madder dye
Answer:
(b) yellow dye

Question 97.
Which one of the following is the IUPAC name of CH3 – CH2 – CH2CN?
(a) Propiono nitrite
(b) Butane cyanide
(c) Isobutyro nitnie
(d) Butane nitrile
Answer:
(d) Butane nitrile

Question 98.
Which one of the following is formed when methyl magnesium bromide reacts with cyanogen chloride?
(a) methane nitrile
(b) ethane nitrite
(c) Acetamide
(d) Nitro ethane
Answer:
(b) ethane nitrite

Question 99.
The reagent used in the conversion of CH3CONH2 into CH3CN is …………
(a) Br2/KOH
(b) conc. HNO3
(c) Sn/HCI
(d) P2O5
Answer:
(d) P2O5

Question 100.
The product of complete hydrolysis of Ethane nitrite is …………
(a) Ethane
(b) Ethyl nitrate
(c) Nitro ethane
(d) Acetic acid
Answer:
(d) Acetic acid

Question 101.
What is the name of the reaction that take place between Ethane nitrile and Ethyl propionate?
(a) Coupling reaction
(b) Levine and hauser acetylation
(c) Diazotisation
(d) Acetic acid
Answer:
(b) Levine and hauser acetylation

Question 102.
Which one of the following is formed when methyl iso cyanide ùndergoes acid hydrolysis?
(a) Dimethyl amine + H2O
(b) Acetic acid + Formic acid
(c) Methyl amine + Formic acid
(d) Methyl cyanide + Ammonia
Answer:
(c) Methyl amine + Formic acid

Question 103.
The product formed when methyl isocyanide is heated to 250°C is …………
(a) Methyl amine
(b) Methyl cyanide
(c) Ethyl Cyanide
(d) Amino ethane
Answer:
(b) Methyl cyanide

Question 104.
Which one of the following is used a fuel for cars?
(a) CH3NO2
(b) CH3NH2
(c) CH3N
(d) CH3NC
Answer:
(a) CH3NO2

Question 105.
Chloropicrin is used as ……….
(a) antiseptic
(b) analgesic
(c) insecticide
(d) fertilizer
Answer:
(c) insecticide

Question 106.
Which one of the following is used as a fuel additive and precursor to explosive?
(a) Nitroglycerine
(b) Nitro methane
(c) Nitro benzene
(d) Nitro ethane
Answer:
(d) Nitro ethane

Question 107.
Which one of the following is known as sweet spirit of nitre?
(a) 10 % solution of methyl nitrite
(b) 4% solution of ethyl nitrite
(c) 10% solution of ethyl nitrite
(d) 40% solution of methanal
Answer:
(b) 4% solution of ethyl nitrite

Question 108.
Which one of the following is used as diuretic?
(a) Nitro methane
(b) Nitrobenzene
(c) ethyl nitrite
(d) Oil of mirbane
Answer:
(c) ethyl nitrite

Question 109.
Which of the following is used to produce lubircating oils in motors and machinery?
(a) Nitro benzene
(b) m – dinitro benzene
(c) 1, 3, 5 – trinitro benzene
(d) Nitro glycerine
Answer:
(a) Nitro benzene

Question 110.
Which of the following is used in the manufacture of aniline, synthetic rubber, dyes and explosives like TNT, TNB?
(a) Nitro ethane
(b) Aminobenzene
(c) Nitro benzene
(d) Benzene diazonium chloride
Answer:
(c) Nitro benzene

Question 111.
Which of the following is used in textile industries and also as a solvent in perfume industries?
(a) Alkyl cyanide
(b) Alkyl iso cyanide
(c) Alkyl iso thio cyanate
(d) Alkyl amine
Answer:
(a) Alkyl cyanide

Question 112.
Which one of the following is used as an anticancer agent used to stomach and colon cancer?
(a) Vitamin C
(b) Cobalamine
(c) mitomycin C
(d) Streptomycin
Answer:
(c) mitomycin C

Question 113.
In the Hoffmann bromamide degradation reaction, the number of moles of KOH and Br2 used per mole of amine produced are …………..
(a) four moles of KOH and two moles of Br2
(b) two moles of KOH and two moles of Br2
(c) four moles of KOH and one moles of Br2
(d) one moles of KOH and one moles of Br2
Answer:
(c) four moles of KOH and one moles of Br2

Question 114.
What is the product obtained in the following reaction?

Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-229
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-228

Question 115.
The reagent with which the following reaction is best accomplished is ………….
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-227
(a) H3PO3
(b) H3PO4
(c) H3PO2
(d) NaHSO3
Answer:
(c) H3PO2

Question 116.
The amine “A” when treated with nitrous acid gives yellow oily substance. The amine “A” is …………
(a) Triethylamine
(b) Trimethylamine
(c) aniline
(d) Ethyl methyl amine
Answer:
(d) Ethyl methyl amine

Question 117.
Which one of the following amide will not undergo Hoffmann bromamide reaction?
(a) CH3CONH2
(b) CH3CONHCH3
(c) C6H5CONH2
(d) CH3CH2CONH2
Answer:
(b) CH3CONHCH3

Question 118.
Replacement of diazonium group by fluorine is known as …………..
(a) Gattennann reaction
(b) Sandmeyer reaction
(c) Baltz – Schiemann reaction
(d) Comberg reaction
Answer:
(c) Baltz – Schiemann reaction

Question 119.
Considering the basic strength of amines in aqueous solution, which are has the smallest pK value?
(a) CH3NH2
(b) (CH3)3N
(c) C6H5NH2
(d) (CH3)3NH
Answer:
(d) (CH3)3NH

Question 120.
Which one of the following is the strongest base in aqueous solution?
(a) Trimethyl amine
(c) Dimethyl amine
(d) methyl amine
(b) Aniline
Answer:
(c) Dimethyl amine

Question 121.
Diethyl amine when treated with nitrous acid yields
(a) Diethyl ammonium nitrite
(b) Ethyl alcohol
(c) N – nitroso diethyl amine
(d) Triethyl ammonium nitrate
Answer:
(c) N – nitroso diethyl amine

Question 122.
Which one of the following on reduction with Lithium aluminium hydride yields a secondary amine?
(a) Methyl iso cyanide
(b) Acetamide
(c) Methyl cyanide
(d) Nitro ethane
Answer:
(a) Methyl iso cyanide

Question 123.
The action of nitrous acid on ethylamine gives
(a) Ethane
(b) ammonia
(c) Ethyl alcohol
(d) Ethyl nitrite
Answer:
(c) Ethyl alcohol

Question 124.
Indicate which nitrogen compound amongst the following would undergo Hoffmann reaction with Br2 and strong KOH to furnish primary amine kNH2.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-232
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-231

Question 125.
The correct order of basicity of the following compounds is …………..
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-230
(a) (ii) > (i) > (iii) > (iv)
(b) (i) > (iii) > (ii) > (iv)
(c) (iii) > (i) > (ii) > (iv)
(d) (i) > (ii) > (iii) > (iv)
Answer:
(b) (i) > (iii) > (ii) > (iv)

Question 126.
Which of the following would be most reactive towards nitration?
(a) Benzene
(b) nitrobenzene
(c) Toluene
(d) Chiorobenzene
Answer:
(b) nitrobenzene

Question 127.
Aniline reacts with acetaldehyde to form.
(a) Schiff’s base
(b) carbylamine
(c) Imine
(d) acetaldoxime
Answer:
(a) Schiff’s base

Question 128.
Which of the following is the strongest base?
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-235
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-234

Question 129.
A primary amine is formed from an amide by the treatment of bromine and alkali. The primary amine has ……………
(a) 1 Carbon atom less than amide
(b) 1 carbon atom more than amide
(c) 1 hydrogen atom less than amide
(d) 1 Hydrogen atom more than amide
Answer:
(a) 1 Carbon atom less than amide

Question 130.
Liebermann’s nitroso reaction is used for testing ………….
(a) 1° amine
(b) 2° amine
(c) 3° amine
(d) all the above
Answer:
(b) 2° amine

Question 131.
A nauseating smell in the carbylamine test for primary amines is due to the formation of …………
(a) iso cyanide
(b) chloroform
(c) cyanide
(d) iso thiocyanate
Answer:
(a) iso cyanide

Question 132.
A positive carbylamine test is given by …………
(a) N, N – dimethyl aniline
(b) 2, 4 – dimethyl aniline
(c) N – methyl – 0 – methyl aniline
(d) p – methyl benzylamine
Answer:
(b) 2, 4 – dimethyl aniline

Question 133.
When primary amine is heated with CS2 in the presence of excess of mercuric chloride, it gives isothiocyanate. This reaction is called ……………..
(a) Hoffmann bromamide reaction
(b) Carbylamine reaction
(c) Perkin’s reaction
(d) Hoffmann mustard oil reaction
Answer:
(d) Hoffmann mustard oil reaction

Question 134.
Diazo – coupling reaction is useful to prepare some
(a) Dyes
(b) proteins
(c) pesticides
(d) plastics
Answer:
(a) Dyes

Question 135.
Carbylamine test is used in the detection of …………
(a) aliphatic 2° amine
(b) Aromatic 1° amine
(c) Aliphatic l amine
(d) both aliphatic and aromatic 1° amine
Answer:
(d) both aliphatic and aromatic 1° amine

Question 136.
Which of the following amine will not react with nitrous acid to give nitrogen?
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-233
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-236

Question 137.
Which of the following compound is expected to be more basic?
(a) Aniline
(b) Methylamine
(c) Ethylamine
(d) Hydroxylamine
Answer:
(c) Ethylamine

Question 138.
Nitro group in Nitro benzene is a ………….
(a) ortho directing group
(b) Meta directing group
(c) Para directing group
(d) ortho and para directing group
Answer:
(b) Meta directing group

Question 139.
Which of the following amines would undergo diazotisation?
(a) CH3NH2
(b) C2H5NH2
(c) C6H5NH2
(d) (CH3)2NH
Answer:
(c) C6H5NH2

Question 140.
Primary amines can be distinguished from secondary and tertiary amines by reacting with.
(a) CHCI3 and alkali
(b) CH3I
(c) CHCl3 alone
(d) Zn dust
Answer:
(a) CHCI3 and alkali

Question 141.
A solution of methylamine …………..
(a) turns blue litmus red
(b) turns red litmus blue
(c) does not effect red or blue litmus
(d) Bleaches litmus
Answer:
(b) turns red litmus blue

Question 142.
Oil of mirbane is ………..
(a) Aniline
(b) Nitro ethane
(c) p – amino azo benzene
(d) Nitro benzene
Answer:
(d) Nitro benzene

Question 143.
Identify the product Z in the series of the reaction ………….
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-237
(a) CH3CHO
(b) CH3CONH2
(c) CH3COOH
(d) CH3CH2NHOH
Answer:
(c) CH3COOH
Solution:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-239

Question 144.
Primary and secondary amines are distinguished by ……….
(a) Br2 / KOH
(b) HCIO4
(c) NH3
(d) HNO2
Answer:
(d) HNO2

Question 145.
Aniline on treatment with excess bromine water gives
(a) Anilinium bromide
(b) O – bromo aniline
(c) 2, 4, 6 – tribromo aniline
(d) p – bromo aniline
Answer:
(c) 2, 4, 6 – tribromo aniline

Question 146.
Which of the following is not used as an explosive?
(a) Trinitro toluene
(b) Trinitro benzene
(c) Trinitro glycerine
(d) Nitro benzene
Answer:
(d) Nitro benzene

Question 147.
Which of the following has a pyramidal structure?
(a) Trimethyl amine
(b) Water
(c) Acetylene
(d) Methane
Answer:
(a) Trimethyl amine

Question 148.
Which one of the following reacts with benzaldehyde to give schiff’s base.
(a) Acidified K2Cr2O7
(b) formaldehyde
(c) Aniline
(d) Potassium cyanide
Answer:
(c) Aniline

Question 149.
Ethyl amine can be prepared by the action of bromine and caustic potash on
(a) Acetamide
(b) propionamide
(c) Formamide
(d) Methyl Eyanide
Answer:
(b) propionamide

Question 150.
Which of the following reaction will not give primary amine?
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-240
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-238

Question 151.
Which of the following compound is the strongest base?
(a) Ammonia
(b) Aniline
(c) Methyl amine
(d) N – methyl aniline
Answer:
(c) Methyl amine

Question 152.
Azo dyes are prepared from ………….
(a) Phenol
(b) Aniline
(c) Benzaldehyde
(d) Both (i) and (ii)
Answer:
(d) Both (i) and (ii)

II. Fill in the blanks.

  1. ………….. is an organic compound needed to maintain the health of nerves, skin and red blood cells.
  2. Plants synthesis and to protect them from being eaten away by insect ………….. and ………….. other animals.
  3. ………….. compounds are the important constituents of explosives, drugs, dyes, fuels, polymers, synthetic rubbers.
  4. Dopamine act as …………..
  5. ………….. dilates blood vessels.
  6. Tertiary nitro alkanes donot exhibit ………….. due to the absence of a-H atom.
  7. Aci form of nitro alkanes gives ………….. colour with ferric chloride.
  8. Aci form of nitro alkanes are otherwise called ………….. or …………..
  9. Laboratory preparation of Nitro ethane from ethyl bromide follows ………….. mechanism
  10. Except ………….. other alkanes gives a mixture of nitro alkanes due to C – C cleavage by nitration of alkanes.
  11. Oxidation of acetaldoxime with ………….. gives 1 – nitro ethane.
  12. ………….. is suspected to cause genetic damage and be harmful to the nervous system.
  13. Nitro benzene on reduction with SnCl2 + KOH gives …………..
  14. Nitrobenzene on alkaline medium reduction gives …………..
  15. Amines posses ………….. geometry.
  16. The nitrogen atom in amine is ………….. hybridised.
  17. Gabriel phthalimide synthesis is used for the preparation of …………..
  18. Ammonolysis of hydroxyl compounds is called ………….. reaction.
  19. Aniline when exposed to air becomes coloured due to …………..
  20. Alkyl amines are stronger base than …………..
  21. Acylation and benzoylation of Aniline aer ………….. reactions.
  22. Libermann’s nitroso test is used to detect …………..
  23. ………….. test is used to identify primary amine.
  24. Direct nitration of aniline gives O and P – nitro aniline along with ………….. due to oxidation.
  25. The conversion of benzene diazonium chloride to benzene by H3PO2 proceeds through ………….. mechanism.
  26. Benzene diazonium chloride when boiled with water gives …………..
  27. The conversion of Benzene diazonium chloride is Biphenyl is called ………….. reaction.
  28. Coupling reaction generally occurs at ………….. position of Benzene ring.
  29. The condensation reaction of esters with nitrites containing a – hydrogen is known as …………..
  30. Chloropicrin is used as an …………..
  31. 4% solution of ethyl nitrite in alcohol is known as …………..
  32. Sweet spirit of nitre is used as …………..
  33. ………….. is used to produce lubricating oils in motors and machinery.
  34. ………….. an anti cancer agent used to treat stomach and colon cancer.
  35. Mitomycin C contains an ………….. ring.
  36. ………….. is used as percursor to explosive.
  37. An organic nitrogen compound ………….. is used as an insecticide.
  38.  ………….. is known as sweet spirit of nitre.
  39.  Chloropicnn ………….. is used as an insecticide.

Answer:

  1. Pyridoxine, vitamin B6
  2. alkaloids, biologically active amines
  3. Nitrogen
  4. Neurotransmitter
  5. Histamine
  6. tautomerism
  7. Reddish brown
  8. Pseudo acids (or) Nitronic acids
  9. SN2
  10. Methane
  11. trifluoroperoxy acetic acid
  12. Nitro ethane
  13. Azobenzene
  14. Hydrazobenzene
  15. Pyramidal
  16. SP3
  17. Aliphatic primary amines
  18. Sabatier – mailhe
  19. Oxidation
  20. Ammonia
  21. Nucleophilic substitution (or) Schotten Baumann
  22. Secondary amine
  23. Carbylamine reaction (or) Hoffmann mustard oil reaction
  24. dark coloured tars
  25. Free radical chain
  26. Phenol
  27. Gomberg
  28. Para
  29. Levine and hauser
  30. insecticide
  31. Sweet spirit of nitre
  32. diuretic
  33. Nitrobenzene
  34. Mitomycin C
  35. Aziridine
  36. Nitro ethane
  37. chloropicrm
  38. 4% solution of ethyl nifrite in alcohol
  39. CCI3NO2

III. Match the Column I and II using the code given below the columns.

Question 1.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-243
Answer:
(a) 3 4 2 1

Question 2.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-241
Answer:
(b) 3 4 1 2

Question 3.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-244
Answer:
(c) 3 4 1 2

Question 4.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-242
Answer:
(a) 4 3 1 2

Question 5.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-245
Answer:
(b) 4 1 2 3

Question 6.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-246
Answer:
(a) 3 4 2 1

Question 7.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-247
Answer:
(a) 3 1 4 2

Question 8.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-250
Answer:
(a) 2 1 4 3

Question 9.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-248
Answer:
(a) 3 4 1 2

Question 10.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-249
Answer:
(a) 4 1 2 3

IV. Assertion and reasons.

Question 1.
Assertion(A): Tertiary nitro alkanes do not exhibit tautomerism.
Reason (R): Tertiary nitro alkanes do not have of α – H atom.
(a) Both A and R are correct and R is explains A
(b) Both A and R are not correct
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is explains A

Question 2.
Assertion(A): Primary and secondary nitroalkanes show an equilibrium mixture of two tautomers namely nitro and aci form.
Reason (R): Both primary and secondary nitroalkanes are having a-H atoms.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are correct but R is not the correct explanation of ofA
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 3.
Assertion(A): Nitro alkanes dissolve in NaOH solution to form a salt.
Reason (R): The α – H atom of 1° and 2° nitroalkanes show acidic character because of the electron withdrawing effect of NO2 group.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are correct but R is not the correct explanation of of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 4.
Assertion(A): 2 – nitro propane is more acidic than nitro mehtane.
Reason (R): When the number of alkyl group attached to a carbon increases, acidity decreases. due to +1 effect of alkyl groups.
(a) Both A and R are correct but R is not the correct explanation of of A
(b) Both A and R are correct and R is the correct explanation of A
(c) A is correct but R is wrong.
(d) A is wrong but R is correct
Answer:
(d) A is wrong but R is correct

Question 5.
Assertion(A): Nitrobenzene cannot be prepared from bromo benzene by action of ethanolic solution of potassium nitrite.
Reason (R): The bromine directly attached to the benzene ring cannot be cleaved easily.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are correct but R is not the correct explanation of of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 6.
Assertion(A): Nitrobenzene undergoes friedel – craft reaction.
Reason (R): Nitrobenzene have strong deactivating – NO2 group.
(a) Both A and R arc correct but R is not the correct explanation of A
(b) Both A and R are correct and R is the correct explanation of A
(c) A is wrong but R ¡s correct
(d) A is correct but R is wrong
Answer:
(c) A is wrong but R ¡s correct

Question 7.
Assertion(A): Amines posses pyramidal geometry.
Reason (R): Nitrogen atoms of amines is trivalent and has four sp3 hybridised orbital. Three sp3 orbitais overlap with orbitais of hydrogen and four sp3 orbitais contain a lone pair of electrons.
(a) Both A and R are correct and R ¡s the correct explanation of A
(b) Both A and R are correct but R is not the correct explanation of A
(c) A is correct but R is wrong.
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R ¡s the correct explanation of A

Question 8.
Assertion(A): The C – N – C bond angle of trimethyl amine is 108°.
Reason (R): The bond angle of C – N – C is due to the repulsion between the bulky methyl groups.
(a) Both A and R are wrong
(b) A is correct and R is wrong
(c) Both A and R are correct and R is the correct explanation of A
(d) Both A and R are correct but R is not the correct explanation of A
Answer:
(c) Both A and R are correct and R is the correct explanation of A

Question 9.
Assertion(A): Aniline cannot be prepared by Gabriel phthalimide synthesis.
Reason (R): Arylhalides do not undergo nucleophilic substitution with the anion formed by phthalimide
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are correct but R is not the correct explanation of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 10.
Assertion(A): Amines have lower boiling point than alcohols.
Reason (R): Nitrogen has lower electronegative value than oxygen and hence the N – H bond is less polar than – OH bond.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are correct but R is not the correct explanation of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 11.
Assertion(A): Tertiary methyl amine is less soluble in water than methyl amine.
Reason (R): Solubility decreases due to the increase in size of the hydrophobic alkyl group.
(a) Both A and R are wrong
(b) A is correct but R is wrong.
(c) Both A and R are correct and R is the correct explanation of A
(d) Both A and R are correct but R is not the correct explanation of A
Answer:
(c) Both A and R are correct and R is the correct explanation of A

Question 12.
Assertion(A): Aniline reacts with acids to form salts and also reacts with electrophiles.
Reason (R): The lone pair of electrons on nitrogen atom in amines makes them basic as well as nucleophilic.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are correct but R is not the correct explanation of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 13.
Assertion(A): Alkyl amines are stronger base than Ammonia.
Reason (R): When a +I gorup like alkyl group is attached to nitrogen increases the electron density on the nitrogen which makes the electron pair readily available for protonation.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are correct but R is not the correct explanation of A
(c) A is wrong but R is correct
(d) A is correct but R is wrong
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 14.
Assertion(A): 2° amines are more basic.
Reason (R): Due to + I effect, steric effect and hydration effect cause 2° amines are more basic.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are correct but R is not the correct explanation of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 15.
Assertion(A): Aromatic amines are less basic than ammonia.
Reason (R): The lone pair of electrons on nitrogen atom in aniline (aromatic amine) gets delocalised over the benzene ring and less available for protonation.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are wrong
(c) A is correct but R is wrong.
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 16.
Assertion(A): Electrophilic substituion in aniline take place at ortho and para position.
Reason (R): The – NH2 group is a strong activating group and lone pair of electrons on the nitrogen atom is in conjugation with benzene ring that increases electron density at ortho and para position.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are correct but R is not the correct explanation of A
(c) A is correct but R is wrong.
(d) Both A and R are wrong
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 17.
Assertion(A): Acylation of amines gives a mono substituted product whereas alkylation of amines gives polysubstituted product.
Reason (R): Acyl group sterically hindered the approach to further acyl group.
(a) Both A and R are wrong
(b) A is correct but R is wrong
(c) Both A and R are correct and R is the correct explanation of A
(d) Both A and R are correct but R is not the correct explanation of A
Answer:
(c) Both A and R are correct and R is the correct explanation of A

Question 18.
Assertion(A): Acetanilide is less basic than anime.
Reason (R): Acetylation of aniline results in the decrease of electron density on nitrogen.
(a) Both A and R are correct and R explains A.
(b) Both A and R are wrong
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R explains A.

Question 19.
Assertion(A): Aromatic 1° amines can be prepared by Gabriel phthalimide synthesis.
Reason (R): Aryl halides undergo nucleophilic substitution with the anion formed by phthalimide.
(a) Both A and R are correct and R is explains A
(b) Both A and R are wrong
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(b) Both A and R are wrong

Question 20.
Assertion(A): Aniline does not undergo Friedel – Crafts reaction.
Reason (R): Aniline donates its lone pair of electrons to the Lewis acid AiCl3 to form an adduct which inhibits further electrophilic substitution reaction.
(a) Both A and R are correct and R is explains A.
(b) Both A and R are wrong
(c) A is correct but R is wrong.
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is explains A.

V. Find the odd one out and give the reasons.

Question 1.
Pyridoxine, Dopamine, Histamine, Aspirin.
Answer:
Aspirin:
It is acid derivative and used as medicine whereas other are organic nitrogen compounds used in medicine.

Question 2.
Trinitro glycerine, Glyceryl triacetate, Trinitro benzene, Trinitro toluene
Answer:
Glyceryl triacetate:
It is a an ester of glycerol whereas others are organic nitrogen compounds used in making explosives.

Question 3.
N – methyl methanamine, N – methyl ethanamine, N – phenyl benzamide, N,N – dimethyl methanamine
Answer:
N,N – dimethyl methanamine: It ¡s an example of tertiary amine whereas others are secondary amine.

Question 4.
Propan – 2 – amine, N – ethyl – N – methyl, propan – 2 – amine, N,N – dimethyl methanamine, N, N – diethyl butan – 1 – amine
Answer:
Propan – 2 – amine:
It is a secondary amine whereas others are tertiary amines.

Question 5.
P – hydroxy azo benzene, Hydrazo benzene, P – amino azo benzene, 2 – Phenyl azo – methyl phenol
Answer:
Hydrazo benzene: It is not a dye whereas others are dyes.

Question 6.
Methyl ISo cyanide, Methyl cyanide, Acetic anhydride, Ethyl amine Nitro ethane
Answer:
Acetic anhydride:
It is an acid derivative whereas others are organic nitrogen compounds.

Samacheer Kalvi 12th Chemistry 13 Organic Nitrogen Compounds 2 Mark Questions and Answers

Question 1.
What is called nitro compound? Give one example.
Answer:
1. Ntiro compounds are considered as the derivatives of hydrocarbons. 1f one of the hydrogen atom of hydrocarbon is replaced by the – NO2 group, the resultant organic compound is called a ntiro compound.

2. E.g., CH3 – CH2 – NO2. Nitro ethane

Question 2.
Define Tautomerism. Give example. Why tertiary nitro alkanes do not ethibit tautomerism?
Answer:
1. Tautomerism is an isomerism in which the isomers change into one another with great ease of shifting of proton so that they exist together in equilibrium.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-251

2. Tertiary nitro alkanes do not exhibit tautomerism due to absence of a-H atom.

Question 3.
Differentiate between nitro form and acid form of tautomerism of nitro methane.
Answer:
Nitro form

  1. Less acidic
  2. Dissolves in NaOH slowly.
  3. Decolourises FeCl3 solution.
  4. Electrical conductivity is low.

Aci form

  1. More acidic and also called pseudo acids (or) Nitrolic acids.
  2. Dissolves in NaOH instantly.
  3. With FeCI3 gives reddish brown colour.
  4. Electrical conductivity is high.

Question 4.
Compare the acid strength of the following compounds

  1. Nitro methane
  2. Nitro ethane
  3. 2 – nitro propane.

Answer:
1. The α – H atom of 10 and 20 nitroalkanes show acidic character because of the electron withdrawing effect of NO2 group.

2. Nitroalkanes dissolve in NaOH solution to form a salt.

3. When the number of alkyl group attached to a carbon increases, acidity decreases. due to +1 effect of alkyl groups.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-253

Question 5.
Nitro benzene cannot be prepared from Bromo benzene by direct nitration. Give reason.
Answer:
Nitro benzene cannot be prepared from Bromo benzene because the bromine directly attached to the benzene ring cannot be cleaved easily.

Question 6.
How would you convert Acetaldoxime into Nitroethane?
Answer:
Oxidation of acetaldoxime and with trifluoro peroxy acetic acid gives nitroethane.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-252

Question 7.
How is nitrobenzene from benzene?
Answer:
When benzene is heated with a nitrating mixture (Con.HNO3 + Con.H2SO4), at 330 K, electrophilic substitution takes place to form nitro benzene.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-256

Question 8.
How will you prepare p – dinitrobenzene from p – nitroanlline?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-255

Question 9.
How is amino group can be directly converted into nitro group? Explain with an example.
Answer:
Amino group can be directly converted into nitro group using caro’s acid (H2SO5) (or) persuiphuric acid (H2S2O8) (or) peroxytrifluro acetic acid (F3C.COOOH) as oxidising agent.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-257

Question 10.
Explain the action of tin and hydrochloric acid with ethyl nitrite.
Answer:
Ethyl nitrite on reduction with Sn / HCI gives ethanol.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-254

Question 11.
Explain about the acid (or) basic hydrolysis of ethyl nitrite.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-262

Question 12.
What is Chioropicrin? How is ¡t prepared? Give its uses.
Answer:
CCI3NO2 is Chioropicrin. It is prepared from nitro methane with Cl2 in the presence of NaOH. The a – H atom of nitroalkanes are successively replaced by halogen atoms. It is used as an insecticide.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-259

Question 13.
Explain – Nef carbonly synthesis.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-260

Question 14.
What happens when nitrobenzene Is treated with Ni (or) Pt (or) LiAIH4?
Answer:
Nitrobenzene undergoes reduction with Ni (or) Pt (or) LiAlH4 to give aniline.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-261

Question 15.
Write a note about structure of Amines.
Answer:
1. Nitrogen atom of amines is trivalent and carries a lone pair of electron and sp3 hybridised, out of the four sp3 hybridised orbitais of nitrogen, three sp3 orbitais overlap with orbitais of hydrogen (or) alkyl groups of carbon, the fourth sp3 orbital contains a lone pair of electron. Hence, amines posses pyramidal geometry.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-258

2. Due to presence of lone pair of electron C – N – H (or) C – N – Cbond angle is less than the normal tetrahedral bond angle 109.5v. For example, the C – N – C bond angle of trimethylamine is 108°. This is due to the repulsion between the bulky methyl groups.

Question 16.
How would you convert Nitroethane to ethanamine?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-267

Question 17.
Explain the action of Pt (or) Sn/HCI with nitrobenzene.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-263

Question 18.
Explain mendlus reaction.
Answer:
Reduction of alkyl or aryl cyanides with Na / C2H5OH is used as a reducing agent is called mendius reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-266

Question 19.
Explain the action of sodium amalgum and ethanol with Methyl isocyanide.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-265

Question 20.
What happens when sodium azide is treated with methyl bromide?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-264

Quesion 21.
How would you convert chiorobenzene to aniline?
Answer:
When chiorobenzene is heated with alcoholic ammonia, aniline is obtained.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-269

Question 22.
Explain Sabatier – MalIhe method.
Answer:
when vapour of an alcohol and ammonia are passed over alumina, W2O5 (or) silica at 400°C, all types of amines are formed. This method is called Sabatier – Mailhe method.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-268

Question 23.
Convert phenol into aniline.
Answer:
Phenol reacts with ammonia at 300°C in the presence of anhydrous ZnCl2 to give aniline.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-270

Question 24.
Compare the boiling points of 10, 2° and 3° amInes.
Answer:
1. The boiling point of various amines follows the order,
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-271

2. Due to the polar nature of primary and secondary amines, can form intermolecular hydrogen bonds using their lone pair of electron on nitrogen atom. However, tertiary amines do not form intermolecular hydrogen bond and they have lower boiling point than 1° and 2° amines.

Question 25.
Aniline is basic in nature. Justify this statement.
Answer:
The lone pair of electrons on nitrogen atom in aniline makes it base. Aniline reacts with mineral acids to form salt.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-272

Question 26.
Alkyl amines are stronger bases than ammonia. Justify this statement.
Answer:
When a + I group like and alkyl group is attached to the nitrogen increase the electron density on nitrogen which makes the electron pair readily available for protonation. Hence alkyl amines are stronger than ammonia.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-274

Question 27.
Explain the action of acretyl chloride with ethyl amine?
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-277

Question 28.
What happens when ethylamine reacts with nitrous acid?
Answer:
Ethylamine reacts with nitrous acid to give ethyl diazonium chloride, which is unstable and it is converted to ethanol by liberating N2.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-276

Question 29.
Explain the action of nitrous acid with N – methyl aniline.
Answer:
N – methyl aniline react with nitrous acid to give N – nitroso amine as yellow oily liquid which is insoluble in water.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-273

Question 30.
Explain the action of nitrous acid with trimethyl amine.
Answer:
Aliphatic tertiary amine reacts with nitrous acid to form trialkyl ammonium nitrite salt, which is soluble in water.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-275

Question 31.
What happens when nitrous acid is treated iith N, N – dimethyl aniline?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-278

Question 32.
Explain Hoffmann mustard oil reaction. (or) Explain the action of CS2 with aniline.
Answer:
When aniline is treated with CS2, or heated together, S – diphenylthio urea is formed, which on boiling with strong HCI , phenyl isothiocyanate (phenyl mustard oil), is formed.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-281
The above reaction is known as Hoffmann mustard oil reaction.

Question 33.
Explain the action of Br2water with aniline.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-280

Question 34.
How would you prepare p – bromo aniline from aniline?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-279

Question 35.
How would you prepare p – nitro from aniline?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-282

Question 36.
Explain the action of hypophosphrous acid with Benzene diazonium chloride. (or) Explain the action of ethanol with benzene diazonium chloride.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-283

Question 37.
Explain Gattermann reaction.
Answer:
Gattermann reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-284

Question 38.
How would you get iodo benzene form benzene diazonium chloride.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-286

Question 39.
Explain Baltz – schiemann reaction.
Answer:
When benzene diazonium chloride is treated with fluoroboric acid, benezene diazonium tetra fluoroborate is precipitated which on heating decomposes to give fluorobenzene.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-285

Question 40.
Convert Benzene diazonium chloride into phenol.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-287

Question 41.
StartIng form Benzene diazonium chloride, how will you get Nitrobenzene?
Answer:
When benzene diazonium chloride is treated with fluoroboric acid we get diazonium fluoroborate which on treated with sodium nitrite solution in the presence of copper, nitrobenzene is obtained.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-289

Question 42.
Convert benzene diazonium chloride to benzoic acid
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-291

Question 43.
Explain the action of SnCl2 and HCl with benzene diazonium chloride.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-1.0

Question 44.
Starting from benzene diazonium chloride, how would you get bright organge azo dye?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-288

Question 45.
Write the structural formula and TUPAC name of the following compounds.

  1. Isobutyl nitrite
  2. Benzo nitrile

Answer:
1. Isobutyl nitrite
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-294
2 – methyll propane nitrile

2. Benzo nitrile C6H5CN Benzene carbo nitrile

Question 46.
Draw the structural formula of

  1. 3 – cyano butanoic acid
  2. 2 – bromo – 3 – chloro – 3 – methyl pentane nitrile.

Answer:
1. 3 – cyano butanoic acid
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-296

2. 2 – bromo – 3 – chloro
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-293
– 3 – methyl pentane nitrile

Question 47.
How will you get propane nitrile from ethyl bromide?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-295

Question 48.
Starting from methyl magnesium bromide, how would you obtain ethane nitrile?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-292

Question 49.
Explain thrope nitrite condensation.
Answer:
Self condensation of two molecules of alkyl nitrile in the presence of sodium to form iminonitrile is called Thrope nitnie condensation.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-298

Question 50.
Explain Levine and hauser acetylation.
Answer:
The nitrites containing α – hydrogen also undergo condensation with esters in the presence of sodamide in ether to form ketoriitriles. This reaction is known as Levine and hauser acetylation.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-297

Question 51.
How would you prepare the following compounds by carbylamines reaction.

  1. Methyl isocyanide
  2. Phenyl isocyanide

Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-299

2.  Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-302

Question 52.
Complete the following reactions.
 Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-301
Answer:
 Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-303

Question 53.
How is methyl isocyanide changed to methyl cyanide?
Answer:
 Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-300

Question 54.
What are the uses of nitrobenzene?
Answer:

  1. Nitro benzene is used to produce lubricating oils in motors and machinery.
  2. It is used in the manufacture of dyes, drugs, pesticides, synthelic rubber, aniline and explosives like TNT, TNB.

Question 55.
Primary amines have higher boiling points than tertiary amines why?
Answer:
Due to the presence of two H – atom on N – atoms of primary amines they undergo extensive intermolecular H – bonding while tertiary amines due to the absence of a H – atom on the N – atom do not undergo H – bonding. As a result primary amines have higher boiling points than tertiary amines.

Question 56.
How is m – nitroaniline obtained from nitrobenzene?
Answer:
 Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-304

Question 57.
How is aniline obtained from benzoic acid?
Answer:
 Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-305

Question 58.
How will you convert benzene into aniline?
Answer:
 Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-308

Question 59.
How will you distinguish between.
 Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-306
Answer:
1. By reacting with NaNO2 and HCl at the temperature of around 0 to 5°C, Aniline will from diazonium salt. CH3NH2 will form methanol and bubbles of N2 gas will come out of the solution.

2. By Hinsberg’s reagent, C6H5SO2CI(CH3)3N will not react. (CH3)2NH will form a product which is insoluble in alkali.

Question 60.
Account for any two of the following.

  1. Amines are basic substances while amides are neutral.
  2. Aromatic amines are weaker bases than aliphatic amines.

Answer:
1. In amines alkyl group is an electron releasing group which increases the electron density on nitrogen thus making them basic whereas in amides
 Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-307
group is electron withdrawing, therefore they are neutral.

2. It is because aryl group is an electron withdrawing group which decreases electron density on nitrogen atom, making them less basic whereas alkyl group is electron releasing which makes alkylamines more basic.

Question 61.

  1. Assign a reason for the following statements – Alkylamines are stronger bases than arylamines.
  2. How would you convert methylamine into ethylamine?

Answer:
1. It is because in arylamines the – NH2 group is attached directly to the benzene ring. It results in the unshared electron pair on nitrogen atom to be in conjugation with the benzene ring and thus making it less available for protonation whereas alkyl group are electron releasing group.

2.  Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-311

Question 62.

  1. How will you convert an alkyl halide to a primary amine whose molecule has one carbon atom more than the used alkyl halide molecule?
  2. Why are amines more basic than the comparable alcohols.

Answer:
1.
 Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-312

2. Due less electronegativity of oxygen atom as compared to nitrogen, amines are more basic than alcohols.

Question 63.
Aniline gets coloured on standing in air for a long time. Why?
Answer:
Due to strong electron – donating effect (+ R effect) of NH2 group, the electron density on the benzene ring increases. As a result, aniline is easily oxidised on standing in air for a long time to form coloured products.

Question 64.
CH3CONH2 is a weaker base than CH3CH2NH2. Why?
Answer:
Due to resonance, the lone pair of electrons on the nitrogen atom in CH3CONH2 is delocalised over the keto group. There is no such effect ip CH3CH2NH2. Due to reduction in electron density on N – atom of CH3CONH2, it is a weaker base than CH3CH2NH2.

Question 65.
Write chemical equation for the following conversions:

  1. CH3CH2 – Cl into CH3CH2CH2 – NH2
  2. C6H5 – CH2 – Cl into C6H5CH2CH2NH2

Answer:
1.  Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-309

2.  Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-310

Samacheer Kalvi 12th Chemistry 13 Organic Nitrogen Compounds 3 Marks Questions and Answers

Question 1.
Write about the classification of organic nitro compounds.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-107

2. Draw the structural formula of the following compounds.

  1. 2 – methyl – 1 – nltropropane
  2. 2, 2 – dimethyl – 1 – nitropropane
  3. Nitrobenzene

Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-108 2 – methyl – 1 – nitropropane
2. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-109 2, 2 – dimethyl – 1- nitropropane
3. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-110 Nitrobenzene

Question 3.
Draw the structural formula of the following compounds.

  1. 2 – nitro – 1 – methyl benzene
  2. 1, 3, 5 – trinitrobenzene
  3. 2 – phenyl – 1 – nitroethane

Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-111    2 – nitro – 1 – methyl benzene
2. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-112 1, 3, 5 – trinitrobenzene
3. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-1132 – phenyl – 1 – nitroethane

Question 4.
Write the possible isomers for the formula C4H9NO2.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-114

Question 5.
How would you prepare nitro ethane from the following compounds?

  1. CH3 – CH2Br
  2. CH3 – CH3

Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-115
2. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-116

Question 6.
Mention any two methods of preparation of nitro methane.
Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-117
2. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-118

Question 7.
Explain the

  1. acid medium reduction
  2. neutral medium reduction of Nitromethane.

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-119

Question 8.
What happens when hydrochloric acid is treated with

  1. Nitro ethane
  2. 2 – nitropropane
  3. 2 – methyl – 2 – nitro propane

(or)
How would you distinguish 1°, 2°, 3° nitro compounds?
Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-120
2. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-121
3. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-122

Question 9.
Explain the following reactions using nitro benzene.

  1. Chlorination
  2. Nitration
  3. Suiphonation

Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-123
2. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-124
3. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-125

Question 10.
Give the structural formula and IUPAC name of the following compounds.

  1. Isopropvl amine
  2. Allyl amine
  3. Hexamethyl diamine

Answer:
1. Isopropvl amineSamacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-126  Propan – 2 – amine
2. Allyl amine Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-127  Prop – 2 – en – 1 – amine
3. Hexamethyl diamine Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-128 Hexane 1, 6 – diamine

Question 11.
Draw the structural formula and write the IUPAC name of

  1. Methyl isopropyl amine
  2. Diethyl butyl amine
  3. Ethyl methyl ispropylamine

Answer:
1. Methyl isopropyl amine:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-129
N – methyl propan – 1 – amine

2. Diethyl butyl amine:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-130
N, N – diethyl butan – 1 – amine

3. Ethyl methyl ispropylamine:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-131
N – ethyl – N – methyl propan – 2 – amine

Question 12.
Draw the structural formula and write the IUPAC name of …………..

  1. N, N – dimethyl aniline
  2. Benzyl amine
  3. N – methyl benzylamine

Answer:
1. N, N – dimethyl aniline
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-132

2. Benzyl amine
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-133

3. N – methyl benzylamine
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-134

Question 13.
Explain the alkylation reaction of methylamine with equation.
Answer:
Alkylation:
Primary amines reacts with alkyl halides to give successively 2° and 3° amines and quaternary ammonium salts.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-135

Question 14.
Explain about the suiphonation reaction of aniline.
Answer:
Aniline reacts with Conc. H2SO4 to form anilinium hydrogen sulphate which on heating with H2SO4 at 453 – 473K gives p – aminobenzene suiphonic acid, commonly known as suiphanilic acid, as the major product.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-136

Question 15.
Explain Sandmeyer reaction with example.
Answer:
On mixing freshly prepared solution of benzene diazonium chloride with cuprous halides, aryl halides are formed. This reaction is called Sandmeyer reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-137

Question 16.
Write the structural formula and IUPAC name of the following compounds.

  1. Methyl cyanide
  2. Propionitrile
  3. Butyro nitrile

Answer:

  1. CH3CN – Ethane nitrile
  2. CH3 – CH2CN – Propane nitrile
  3. CH3 – CH2 – CH2CN – Butane nitnie.

Question 17.
How would you produce Ethane nitrite form the following compounds?

  1. Acetamide
  2. Ammonium acetate
  3. Acetaldoxime

Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-138
2. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-139
3. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-140

Question 18.
Explain the action of following reagent with ethane nitrile.

  1. Dilute mineral acid
  2. Ni / H2

Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-141
2. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-142

Question 19.
What happens when methyl isocyanide reacts with the following reagents?

  1. Mineral acid
  2. Na + C2H5OH

Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-143
2. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-144

Question 20.
Explain the addition reactions of alkyl Isocyanide with

  1. halogen
  2. sulphur
  3. ozone

Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-145
2. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-146
3. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-147

Question 21.
What are the uses of aliphatic nitro compounds.
Answer:

  1. Nitromethane is used as a fuel for cars.
  2. Chloropicrrn (CCI3NO2) is used as an insecticide
  3. Nitroethane is used as a fuel additive and precursor to explosive and they are good solvents for polymers, cellulose ester, synthetic rubber and dyes etc,

Question 22.
Explain about the structure and uses of Mitomycin.
Answer:

  1. Mitomycin C, and anticancer agent used to treat stomach and colon cancer, contains an aziridine ring.
  2. The aziridine functional group participates in the drug’s degradation by DNA, resulting in the death of cancerous cells.
  3. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-148

Question 23
Complete the following reactions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-149
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-150

Question 24.
Convert Methanamine into Ethanamine.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-151

Question 25.
Convert Ethanamic into Methanamine.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-152

Question 26.
How would you obtain Benzoic acid from aniline?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-153

Question 27.
Complete the following reactions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-154
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-155

Question 28.
Write the reactions of

  1. aromatic and
  2. aliphatic primary amines with nitrous acid.

Answer:
Aromatic primary amines react with HNO2 at 273 – 278 K to form aromatic diazonium salts.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-156
Aliphatic primary amines also react with HNO2 at 273 – 278 K to form aliphatic diazonium salts. But these are unstable even at low temperature and thus decomposes readily to form a mixture of compounds consisting of alkyl chlorides, alkenes and alcohols, out of which alcohols generally predominates.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-157

Question 29
Given plausible explanation for each of the following.

  1. Why are amines less acidic than alcohols of comparable molecular masses?
  2. Why do primary amines have higher boiling point than tertiary amines?
  3. Why are aliphatic amines stronger bases than aromatic amines?

Answer:
1. It is because C2H5O° is more stable than C2H5NH° because oxygen is more electronegative than nitrogen.

2. Due to the presence of two H – atoms on N – atom of primary amines, they undergo extensive intennolecular H – bonding while tertiary amines due to the absence of a H – atoms on the N – atom do not undergo H – bonding. As a result, primary amines have higher boiling point than tertiary amines of comparable molecular masses.

3. It is because there is electron withdrawing, C6H5 group in aromatic amines which makes them less basic than aliphatic amines in which alkyl group is electron releasing.

Question 30.
Account for the following.

  1. Primary amines (R – NH2)have higher boiling point than tertiary amines (R3N).
  2. Aniline does not undergo Friedel – Crafts reaction.
  3. (CH3)2NH Is more basic than (CH3)3N in an aqueous solution.

Answer:
1. Due to maximum intermolecular hydrogen bonding in primary amines (due to presence of more number of H – atoms), primary amines have higher boiling point in comparison to tertiary amines.

2. Aniline does not undergo Friedel-Crafts reaction due to acid-base reaction. Aniline and a Lewis Acid / Protic Acid, which is used in Friedel-crafts reaction.

3. In (CH3)3N there is maximum steric hindrance and least solvation but in (CH3)2NH the solvation is more group; di-methyl amine is still a stronger base than trimethyl amine.

Question 31.
Write the structures of A,B and C in the following reactions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-158
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-159

Question 32.
Predict, giving reasons the order of basicity of the following compounds.

  1. gaseous phase
  2. In aqueous solution (CH3)3N, (CH3)2NH, CH3NH2, NH3

Answer:
1. In gaseous phase, basic character of amines increases with the increase in the number of electron the releasing alkyl groups due to + I effect so the trend of basic character is 3° > 2° > 1° > NH3. Therefore, (CH3)3N > (CH3)3NH > CH3NH2 > NH3.

2. In aqueous phase, solvation of ammonium cation occurs by warer molecules, greater the size of ion, lesser will be the solvation and lesser will be the stability of ion. So on combining + I effect and solvation effect, in aqueous phase trend changes to 2° > 1° > 3°, (CH3)2NH > CH3NH2 > (CH3)3N > NH3.

Question 33.
Identify A and B in the following reactions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-160
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-161

Question 34.
What happens when. (Write reactions only)

  1. Nitroethane is treated with LiAlH4.
  2. Diazonium chloride reacts with phenol in basic medium.

Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-162
2. Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-163

Question 35.
How would you achieve the following conversions.
Answer:

(i) Nitrobenzene to aniline

(ii) An alkyl halide to a quarternary ammonium salt.

(iii) Aniline to benzonitrile.

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-164

Question 36.
What happens when (write reactions only).

(i) Nitropropane is treated with LiAlH4.
(ii) Ethyl lsocyañide undergoes hydrolysis.
(iii) Benzene diazonium chloride reacts with phenol i basic medium.

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-165

Question 37.
Identify A and B in the following reactions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-166
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-167

Question 38.
Identify A and B in the following reactions
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-168
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-169
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-170

Question 39.
A compound ‘x’ having molecular formula C3H7NO reacts with Br2 in the presence of KOH to give another compound ‘y’. The compound ‘y’ reacts with HNO2 to form ethanol. and N2 gas. Identify the compounds x andy and write the reactions involved.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-171

Question 40.
An organic compound ‘A’ having molecular formula C3H5N on hydrolysis gave a nother compound ‘B’ The compound ‘B’ on treatment with HNO2 gave ethyl alcohol. ‘B’ on warming with CHCI3 and alcoholic caustic potash gave an offensive smelling substance ‘C’. Identify ‘A’, ‘B’ and ‘C’.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-172

Samacheer Kalvi 12th Chemistry 13 Organic Nitrogen Compounds 5 Mark Questions and Answers

Question 1.
Explain the various reduction reactions of nitrobenzene.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-173
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-174

Question 2.
What happens when nitrous acid react with
(i) Ethyl amine
(ii) Aniline
(iii) N – methyl aniline
(iv) Trimethyl amine
(v) N, N – dimethyl aniline
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-175

Question 3.
Starting from Benzene diazonium chloride, how would you prepare
(i) Benzene
(ii) Phenol
(iii) Nitro benzene
(iv) Benzolc acid
(v) Fluorobenzene
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-176

Question 4.
Starting from Benzene diazonium chloride, how would you prepare
(i) Biphenyl
(ii) Phenyl hydrazine
(iii) p – hydroxy azo benzene
(iv) p – amino azo benzene
(v) Chioro benzene
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-177

Question 5.
Convert aniline into the following compounds.
(i) N – phenyl benzamide
(ii) Phenyl isothiocyanate
(iii) 2, 4, 6 – tribromo aniline
(iv) Sulphanilinic acid
(v) Phenyl isocyanide
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-178

Question 6.
An organic compound (A) of molecular formula C6H7N on reaction with sodium nitrite and hydrochloric acid at 0°C gives (B) of formula C6H5N2Cl. (B) on treatment with cuprous cyanide give (C) of formula C7H5N. (C) on reaction with sodium and ethanol gives (D) of formula C7H9N. (D) on reaction with nitrous acid gives (E) of molecular formula C7H8O. Identify A, B, C, D and E and explain the reactions involved.
Answer:
1. (A) is identified as Aniline from the molecular formula.
2. Aniline on reaction with sodium nitrite and hydrochloric acid at 0°C, diazotisation take place and the product (B) formed is benzene diazonium chloride.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-179

3. Benzene diazonium chloride on treatment with CuCN produces (C) as cyano benzene.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-180

4. Cyano benzene on reaction with Na and C2H5OH undergoes reduction reaction to give (D) as benzvlamine.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-181

5. Benzylamine on treatment with nitrous acid gives benzyl alcohol as (E).
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-182

Question 7.
Complete the following reactions and identify the A, B and C in these reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-183
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-184

Question 8.
An aromatic compound ‘A’ on treatment with aqueous ammonia and heating forms compound ‘B’ which on heating with Br2 and KOH forms a compound ‘C’ of molecular formula C6H7N. Write the structures and IUPAC names of compound A, B and C.
Answer:
Step – 1: To find out the structure of compounds ‘B’ and ‘C’.
1. Since compound ‘C’ with molecular formula C6H7N is formed from compound ‘B’ on treatment with Br2 + KOH (i.e., Hoffmatm bromamide reaction). Therefore, compound ‘B’ must be an amide and ‘C’ must be an amine. The only amine having the molecular formula C6H7N is C6H5NH2 (i.e., aniline or benzenamine).

2. Since ‘C’ is aniline, therefore, the amide from which it is formed must be benzamide (C6H5CONH2). Thus, compound ‘B’ is benzamide. The chemical equation showing the conversion of ‘B’ to ‘C’ is
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-185

Step – 2:
To find out the structure of compound ‘A’. Since compound ‘B’ is formed from compound ‘A’ by treatment with aqueous ammonia and heating. Therefore, compound ‘A’ must be benzoic acid or benzenecarboxylic acid.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-186

Question 9.
An aromatic compound ‘A’ of molecular formula C7H7ON undergoes a series of reactions as shown below. Write the structures of A,B,C, D and E in the following reactions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-187
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-188

Question 10.
Write reactions and conditions required for the following conversions.
(i) Aniline to benzene
(ii) Methylamine to methylcyanide
(iii) Propanenitrile to ethylamine
(iv) m – Bromoaniline to m – bromophenol
(v) Nitrobenzene to 2, 4, 6 – tribromoaniline.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-189

Question 11.
A compound ‘A’ of molecular formula C3H7O2N on reaction with Fe and cone. HCI gives a compound ‘B’ of molecular formula C3H9N. Compound ‘B’ on treatment with NaNO2 and HCI gives another compound ‘C’ of molecular formula C3H8O. The compound ‘C’ has molecular formula, C3H8O. The compound ‘C’ gives effervescence with Na. On oxidation with CrO3, the compound ‘C’ gives a saturated aldehyde containing three carbon atoms. Deduce the structures of A, B and C and write the equations for the reaction involved.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-190

Question 12.
Identify compounds A, B and C in the following reactions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-191
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-192

Question 13.
A aromatic hydrocarbon (A) of molecular formula C6H6 reacts with Conc.HNO3 and Conc. H2SO4 gives (B) of formula C6H5O2N. (B) on reaction with Sn/HCI gives (C) of formula C6H7N which answers carbylamine reaction. (C) on treatment with chloroform and alkali gives (D) of formula C7H5N. Identify A, B, C, D and explain the reactions involved.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-193

Question 14.
Convert the following.
(i) Nitro benzene → Benzene
(ii) Benzene → Benzoic acid

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-194

Common Errors

  1. TUPAC name of nitro compounds.
  2. If the formula ends as – NO2, the students always think of nitro only.
  3. Reducing agents may be different for different medium.
  4. Basic character of amines is always difficult to remember.
  5. Cyanide and isocyanide formula may get confusing.

Rectifications

1. Both common name and IUPAC names are same for aliphatic and aromatic nitro compounds.

2. – NO2 may be
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-195

3.

  • Acid medium reducing agent: Sn / HCI
  • Neutral medium reducing agent: Zn + NH4CI
  • Basic medium reducing agent: Zn / NaOH
  • Catalytic reducing agent: Ni, Pt, LiAlH4

4. 2° amine > 3° amine > 1° amine > NH3
Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-196
Alkyl group is connected to Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-197 C – Cyanide. If alkyl group connected to Samacheer Kalvi 12th Chemistry Solutions Chapter 13 Organic Nitrogen Compounds-198 Isocyandie.

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Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules

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Tamilnadu Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules

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Samacheer Kalvi 12th Chemistry Chapter 14 Biomolecules Textual Evaluation Solved

Samacheer Kalvi 12th Chemistry Biomolecules Multiple Choice Questions

Question 1.
Which one of the following rotates the plane polarized light towards left?
(a) D(+) Glucose
(b) L(+) Glucose
(c) D(-) Fructose
(d) D(+) Galactose
Answer:
(c) D(-) Fructose

Question 2.
The correct corresponding order of names of four aldoses with configuration given below Respectively is ………………..
(a) L – Erythrose, L – Threose, L – Erythrose, D – Threose
(b) D – Threose, D – Erythrose, L – Thrcose, L – Erythrose
(c) L – Etythrose, L – Threose, D – Erythrose, D – Threose
(d) D – Erythrose, D – Threose, L – Erythrose, L – Threose
Answer:
(d) D – Erythrose, D – Threose, L – Erythrose, L – Threose

Question 3.
Which one given below is a non-reducing sugar?
(a) Glucose
(b) Sucrose
(c) maltose
(d) Lactose
Answer:
(b) Sucrose

Question 4.
Glucose(HCN) Product (hydrolysis) Product (HI + Heat) A, the compound A is ………………..
(a) Heptanoic acid
(b) 2 – lodohexane
(c) Heptane
(d) Heptanol
Answer:
(a) Heptanoic acid

Question 5.
Assertion: A solution of sucrose in water is dextrorotatory. But on hydrolysis in the presence of little hydrochloric acid, it becomes levorotatory.
Reason: Sucrose hydrolysis gives unequal amounts of glucose and fructose. As a result of this change in sign of rotation is observed.
(a) If both accretion and reason are true and reason is the correct explanation of assertion
(b) If both assertion and reason are true but reason is not the correct explanation of assertion
(c) If assertion is true but reason is false
(d) if both assertion and reason are false
Answer:
(a) If both accretion and reason are true and reason is the correct explanation of assertion

Qustion 6.
The central dogma of molecular genetics states that the genetic information flows from ……………..
(a) Amino acids Protein DNA
(b) DNA Carbohydrates Proteins
(c) DNA RNA Prnteins
(d) DNA RNA Carbohydrates
Answer:
(c) DNA RNA Proteins

Question 7.
In a protein, various amino acids liked together by …………..
(a) Peptide bond
(b) Dative bond
(c) α – Glycosidic bond
(d) β – Glycosidic bond
Answer:
(a) Peptide bond

Question 8.
Among the following the achiral amino acid is …………..
(a) 2 – ethylalanine
(b) 2 – methyiglycine
(c) 2 – hydroxymethyiscrine
(d) Tryptophan
Answer:
(c) 2 – hydroxymethylserine

Question 9.
The correct statement regarding RNA and DNA respectively is ………………
(a) the sugar component in RNA is an arabinose and the sugar component in DNA is ribose
(b) the sugar component in RNA is 2’ – deoxyribose and the sugar component in DNA is arabinose
(c) the sugar component in RNA is an arabinose and the sugar component in DNA is 2’ – deoxyribose
(d) the sugar component in RNA is ribose and the sugar component in DNA is 2’-deoxyribose
Answer:
(d) the sugar component in RNA is ribose and the sugar component in DNA is 2’ – deoxyribose

Question 10.
In aqueous solution of amino acids mostly exists in ……………….
(a) NH2 – CH(R) – COOH
(b) NH2 – CH(R) – COO
(c) H3N – CH(R) – COOH
(d) H3N+ – CH(R) – COO
Answer:
(d) H3N+ – CH(R) – COO

Question 11.
Which one of the following is not produced by body?
(a) DNA
(b) Enzymes
(c) Hormones
(d) Vitamins
Answer:
(d) Vitamins

Question 12.
The number of sp2 and sp3 hybridised carbon in fructose are respectively ……………..
(a) 1 and 4
(b) 4 and 2
(c) 5 and 1
(d) 1 and 5
Answer:
(d) 1 and 5

Question 13.
Vitamin B2 is also known as …………….
(a) Riboflavin
(b) Thiamine
(c) Nicotinamide
(d) Pyridoxine
Answer:
(a) Riboflavin

Question 14.
The pyrimidine bases present in DNA are …………..
(a) Cytosine and Adenine
(b) Cytosine and Guanine
(c) Cytosine and Thiamine
(d) Cytosine and Uracil
Answer:
(c) Cytosine and Thiamine

Question 15.
Among the following L – serine is …………..
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-1
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-2

Question 16.
The secondary structure of a protein refers to ………………
(a) fixed configuration of the polypeptide backbone
(b) hydrophobic interaction
(c) sequence of a-amino acids
(d) α – helical backbone
Answer:
(d) α – helical backbone

Question 17.
Which of the following vitamins is water soluble?
(a) Vitamin E
(b) Vitamin K
(c) Vitamin A
(d) Vitamin B
Answer:
(b) Vitamin K

Question 18.
Complete hydrolysis of cellulose gives ……………
(a) L – Glucose
(b) D – Fructose
(c) D – Ribose
(d) D – Glucose
Answer:
(d) D – Glucose

Question 19.
Which of the following statement is correct?
(a) Ovalbumin is a simple food reserve in egg-white
(b) Blood proteins thrombin and fibrinogen are involved in blood clotting
(c) Denaturation makes protein more active
(d) Insulin maintains the sugar level of in the human body
Answer:
(c) Denaturation makes protein more active

Question 20.
Glucose is an aldose. Which one of the following reactions is not expected with glucose?
(a) It does not form oxime
(b) It does not react with Grignard reagent
(c) It does not form osazones
(d) It does not reduce tollens reagent
Answer:
(b) It does not react with Grignard reagent

Question 21.
If one strand of the DNA has the sequence ‘ATGCTTGA’, then the sequence of complementary strand would be ……………..
(a) TACGAACT
(b) TCCGAACT
(c) TACGTACT
(d) TACGRAGT
Answer:
(a) TACGAACT

Question 22.
Insulin, a hormone chemically is ………….
(a) Fat
(b) Steroid
(c) Protein
(d) Carbohydrates
Answer:
(c) Protein

Question 23.
a – D (+) Glucose and ß – D (+) glucose are ………………..
(a) Epimers
(b) Anomers
(c) Enantiomers
(d) Conformational isomers
Answer:
(b) Anomers

Question 24.
Which of the following are epimers?
(a) D(+) – Glucose and D(+) – Galactose
(b) D(+) – Glucose and D(+) – Mannose
(c) Neither (a) nor (b)
(d) Both (a) and (b)
Answer:
(d) Both (a) and (b)

Question 25.
Which of the following amino acids are achiral?
(a) Alanine
(b) Leucine
(c) Proline
(d) Glycine
Answer:
(a) Alanine

II. Answer the following questions.

Question 1.
What type of linkages hold together monomers of DNA?
Answer:

  1. Phospho diester linkages hold together monomers of DNA
  2. Phosphoric acid forms phospho diester bond between neucleotides
  3. The sugar – phosphate linkage forms the backbone of each strand of DNA.

Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-3

Question 2.
Give the differences between primary and secondary structure of proteins.
Answer:
Primary structure of proteins

  1. Linear sequence of amino acids
  2. Composed of peptide bonds formed between amino acids.
  3. Formed during translation.
  4. Involved in post – translational modifications.

Secondary structure of proteins

  1. Folding of the peptide chain into an a-helix and 13-sheet.
  2. Encompasses hydrogen bonds
  3. Forms collagen, elastin action, myosin, and keratin – like fibres.
  4. Involved in forming structures such as cartilages, ligaments, skins etc.

Question 3.
Name the Vitamins whose deficiency cause

  1. rickets
  2. scurvy

Answer:

  1. Vitamin – D deficiency causes rickets disease.
  2. Vitamin – C deficiency causes scurvy disease.

Question 4.
Write the Zwitter ion structure of alanine.
Zwitter ion structure of alanine
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-4

Question 5.
Give any three difference between DNA and RNA.
Answer:
DNA

  1. It is mainly present in nucleus, mitochondria and chloroplast .
  2. It contains deoxyribose sugar
  3. Base pair A = T. G = C
  4. Double stranded molecules
  5. Its life time is high
  6. it is stable and not hydrolysed easily by alkalis
  7. It can replicate itself

RNA

  1. It is mainly present in cytoplasm, nucleolus and ribosomes
  2. It contains ribose sugar
  3. Base pair A = U. C = G
  4. Single stranded molecules
  5. It is Short lived
  6. It is unstable and hydrolyzed easily by alkalis
  7. It cannot replicate itself. It is formed from DNA.

Question 6.
Write a short note on peptide bond.
Answer:
1. The amino acids are linked covalently by peptide bonds.

2. The carbonyl group of the first amino acid react with the amino group of the second amino acid to give an amide linkage (- CONH) between these aminoacids. This amide linkage is called peptide bond.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-5

3. The resulting compound is called a dipeptide. Because, two amino acids are inovived for getting one peptide bond.

4. If large number of amino acids combined through peptide bond, the resulting giant molecule is called a protein.

5. The amino end of the peptide is known as N-terminal, while the carboxy end is called C – terminal.

Question 7.
Give two difference between Hormones and vitamins.
Answer:
hormones

  1. Hormones are produced in the endocrine or ductless glands.
  2. Hormones are not stored in the body. These are produced as and when required.
  3. They are effective in low concentration. Their excess or deficiency may cause hormonal disorders.
  4. Hormones influence the genes to produce specific enzymes required during metabolism.
  5. Example: Insulin

Vitamins

  1. Vitamins (except Vitarnin – D) are not produced in the body. Vitamin must be supplied in the diet.
  2. Vitamins are stored in the body upto certain extent.
  3. They are needed in small quantity. Excess vitamins are excreted. Their deficiency causes
  4. malfunctioning called deficiency diseases or avitaminosis.
  5. They act as co-enzymes and help enzymes to perform their function.
  6. Example: Vitamin A, B, C, D, E and K

Question 8.
Write a note on den atu ration of proteins.
Answer:
Denaturation of proteins.
1. In general, protein has a unique three – dimensional structure formed by interactions such as disuiphide bond, hydrogen bond, hydrophobic and electrostatic interactions.

2. These interactions can be disturbed when the protein is exposed to a higher temperature in certain chemicals such urea, alternation of pH, ionic strength etc. It leads to the loss of the three – dimensional structure.

3. The process of a protein losing its higher order structure without losing the primary structure, It is called denaturation of protein. When a protein denatures, its biological function is also lost.

4. Since the primary structure is intact, this process can be reversed in certain proteins. This can happen spontaneously upon restoring the original conditions or with the help of special enzymes called cheperons.

5. Example: Coagulation of egg white by action of heat.

Question 9.
What are reducing and non – reducing sugars?
Answer:
1. Reducing sugars:
Those carbonhydrates which contain free aldehyde or ketonic group and reduces Fehling’s solution and Tollen’s reagent are called reducing sugars. All monosacehaides whether aldose or ketone are reducing sugars.

2. Non – reducing sugars:
Cabohydrates which do not reduce Tollen’s reagent and Fehling’s solution are called non – reducing sugars. Example Sucrose. They do not have free aldehyde group.

Question 10.
Why carbohydrates are generally optically active?
Answer:
Carbohydrates are generally optically active because they have one or more chiral carbon atoms in their molecules. For example, Glucose has four chiral carbons and therefore it is optically active.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-6

Question 11.
Classify the following into monosaccharides, oligosaccharides and polysaccharldes.

  1. Starch
  2. fructose
  3. sucrose
  4. lactose
  5. maltose

Answer:

  1. Starch – Polysaccharides
  2. Furctose – Mono saccharides
  3. Sucrose – Oligo saccharide
  4. Lactose – Oligo saccharide
  5. Maltose – Oligo saccharide

Surcose, Lactose and Maltose are typical disaccharides

Question 12.
How are vitamins classified?
Answer:
Vitamins are classified into two groups based on their solubility in water and in fat. They are,

  1. Water – soluble vitamins
  2. Oil or fat – soluble vitamins

Water – soluble vitamins – Vitamins which dissolve in water are called water soluble vitamins. Examples – Vitamins of B group and Vitamin C Oil or fat – soluble vitamins: Vitamins which dissolve in oils or fat are called oil or fat – soluble vitamins. Examples – Vitamin A, D, E and K

Question 13.
What are hormones? Give examples.
Answer:
Hormone is an organic substance that is sëcreted by one tissue into the blood stream and induces a physiological response in other tissues. It is an inter cellular signaling molecule. Virtually every process is a complex organism is regulated by one or more hormones. Example, insulin, epinephrine, estrogen, androgen etc.

Question 14.
Write the structure of all possible dipeptides which can be obtained from glycine and atanine.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-7
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-8
Therefore two dipeptides structures are possible from glycine and alanine. They are

  1. glycyl alanine and
  2. Alanyl glycine

Question 15.
Define enzymes.
Answer:
There are many biochemical reactions that occur in our living cells. Digestion of food and harvesting the energy from them, and synthesis of necessary molecules required for various – cellular functions are examples for such reactions. All these reactions are catalysed by special proteins called enzymes.
(or)
Enzymes are bio catalysts produced by the living cells which catalyse many biochemical reactions in animal and plant bodies. They are more specific in their action.

Question 16.
Write the structure of – D (+) glucopyranose.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-9

Question 17.
What are different types of RNA which are found in cell?
Answer:
RNA molecules are classified according to their structure and function into three major types.

  1. Ribosomal RNA (r – RNA)
  2. Messenger RNA (m – RNA)
  3. Transfer RNA (t – RNA)

r-RNA:
rRNA is mainly found in cytoplasm and in ribosomes, which contain 60% RNA and 40% protein. Ribosomes are the sites at which protein synthesis takes place.

t – RNA:
tRNA molecules have lowest molecular weight of all nucleic acids. They consist of 73 – 94 nucleotides in a single chain. The function of tRNA is to carry amino acids to the sites of protein synthesis on ribosomes.

m – RNA:
mRNA is present in small quantity and very short lived. They are single stranded, and their synthesis takes place on DNA. The synthesis of mRNA from DNA strand is called transcription. mRNA carries genetic information from DNA to the ribosomes for protein synthesis.

Question 18.
Write a note on formation of – helix.
AnsweR:
1. In the α – helix sub – structure, the aminoacids are arranged in a right handed helical (spiral) structure and are stabilised by the hydrogen bond between the carbonyl oxygen one aminoacid (nth residue) with amino hydrogen of the fifth residue (n + 4th residue)

2. The side chains of the residues protrude outside of the helix. Each turn of an α – helix contains about 3.6 residues and is about 5.4 A long.

3. The amino acid proline produces a line in the helical structure and often called as a helical breaker due to its rigid cyclic structure.

4. Many fibrous proteins such as ct-Keratin in hair, nails, wool, skin and myosin in muscles have α – helix structure. Stretching property of human hair is due to the helical structure of α – keratin in hair.

5. Structure of a-helix.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-10

Question 19.
What are the functions of lipids in living organism?
Answer:

  1. Lipids are the integral component of cell membrane. They are necessary of structural integrity of the cell.
  2. The main function of triglycerides in animals is as an energy reserve. They yield more energy than carbohydrates and proteins.
  3. They act as protective coating in aquatic organisms.
  4. Lipids of connective tissue give protection to internal organs.
  5. Lipids help in the absorption and transport of fat soluble vitamins.
  6. They are essential for activation of enzymes such as lipases.
  7. Lipids act as emulsifier in fat metabolism.

Question 20.
Is the following sugar, D – sugar or L – sugar?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-11

Samacheer Kalvi 12th Chemistry Biomolecules Additional Questions

Samacheer Kalvi 12th Chemistry Biomolecules 1 mark Questions and Answers

I. Choose the best answer.

Question 1.
Which of the following is the most abundant organic compounds in every living organism?
(a) Fats
(b) Proteins
(c) Carbohydrates
(d) Hormones
Answer:
(c) Carbohydrates

Question 2.
What is the general chemical name of carbohydrates?
(a) Poly hydroxy aldehyde or ketones
(b) Poly hydroxy esters
(c) Poly amino acids
(d) Poly carboxylic esters.
Answer:
(a) Poly hydroxy aldehyde or ketones

Question 3.
Which process is utilized in the synthesis of carbohydrates in green plants?
(a) Oxidation
(b) Redox reaction
(c) Photosynthesis
(d) Reduction
Answer:
(c) Photosynthesis

Question 4.
Which of the following compounds are optically active?
(a) Glycine
(b) Carbohydrates
(c) Ethanol
(d) Meso tartaric acid
Answer:
(b) Carbohydrates

Question 5.
Which of the following is optically inactive?
(a) 2 – butanol
(b) Glyceraldehyde
(c) Glucose
(d) Meso tartaric acid
Answer:
(d) Meso tartaric acid

Question 6.
How many isomers are possible for glucose that have 4 asymmetic carbon atoms?
(a) 8 isomers
(b) 16 isomers
(c) 2 isomers
(d) 4 isomers
Answer:
(b) 16 isomers

Question 7.
How many asymmetric carbon atoms are in glucose?
(a) 4
(b) 3
(c) 2
(d) 1
Answer:
(a) 4

Question 8.
Which of the following rotates the plane polarised light in clockwise direction?
(a) L(-) Glucose
(b) D (glucose)
(c) L – fructose
(d) L – Glyceraldehyde
Answer:
(b) D (glucose)

Question 9.
Which one of the following is levorotatory?
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-12
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-13

Question 10.
Which one of the following is not a monosaccharide?
(a) Fructose
(b) Ribose
(c) Erythrose
(d) Maltose
Answer:
(d) Maltose

Question 11.
Which one of the following is a monossachande?
(a) Glucose
(b) Maltose
(c) Surcose
(d) Cellulose
Answer:
(a) Glucose

Question 12.
The number of carbon atoms present in Erythrose is
(a) 6
(b) 4
(c) 3
(d) 5
Answer:
(b) 4

Question 13.
What is the amount of glucose present in human blood?
(a) 150 mg/dI
(b) 50 mg/dl
(c) 100 mg/dl
(d) 1000 mg/dl
Answer:
(c) 100 mg/dl

Question 14.
Which one of the following is called blood sugar?
(a) Erythrose
(b) Ribose
(c) Ribulose
(d) Glucose
Answer:

Question 15.
Acid hydrolysis of starch at high temperature and pressure produces
(a) fructose
(b) glucose
(c) both fructose and glucose
(d) maltose
Answer:
(b) glucose

Question 16.
The other name of glucose is …………
(a) dextrose
(b) blood sugar
(c) aldohexose
(d) all the above
Answer:
(d) all the above

Question 17.
Which one is formed as major product when glucose is on reduction with concentrated HI and red P at 3 73K?
(a) 2 – iodohexane
(b) 3 – iodohexane
(c) n – hexane
(d) 4 – iodohexane
Answer:
(c) n – hexane

Question 18.
Which one of the product is formed when glucose reacts with bromine water?
(a) n – hexane
(b) Gluconic acid
(c) Saccharic acid
(d) Hexanoic acid
Answer:
(c) Saccharic acid

Question 19.
Which one of the following is formed when glucose react with Conc. HNO3?
(a) Gluconic acid
(b) Glutaric acid
(c) Saccharic acid
(d) Hexanoic acid
Answer:
(c) Saccharic acid

Question 20.
Which one of the following will reduce Tollen’s reagent and Fehling’s solution?
(a) Glucose
(b) Fructose
(c) Sucrose
(d) Maltose
Answer:
(a) Glucose

Question 21.
Which of the following form pentacetate with acetic anhydide?
(a) Glucose
(b) Fructose
(c) Lactose
(d) Both a & b
Answer:
(d) Both a & b

Question 22.
Which one of the reagent does not react with glucose?
(a) Acetic anhydride
(b) Tollen’s reagent
(c) Sodium bi suiphite
(d) Bromine water
Answer:
(c) Sodium bi suiphite

Question 23.
The specific rotation of pure α and β (D) glucose are respectively.
(a) 18.7°, 112°
(b) 112°, 18.7°
(c) 90°, 90°
(d) 120°, 20°
Answer:
(b) 112°, 18.7°

Question 24.
Sugar differing in configuration at an asymmetric centre is known as ……………….
(a) epimers
(b) isomers
(c) anomers
(d) monomers
Answer:
(a) epimers

Question 25.
Which enzyme is utilised in the conversion of galactose to glucose?
(a) Maltose
(b) Epimerase
(c) Invertase
(d) Zymase
Answer:
(b) Epimerase

Question 26.
The other name of fructose is ……………
(a) Ketohexose
(b) fruit sugar
(c) levulose
(d) all the above
Answer:
(d) all the above

Question 27.
Hydrolysis of mutin in acidic medium gives ……………
(a) glucose
(b) fructose
(c) both a & b
(d) maltose
Answer:
(b) fructose

Question 28.
Invert sugar is a mixture of equal amount of ……………..
(a) lactose + maltose
(b) diastose + galactose
(c) glucose + fructose
(d) starch + cellulose
Answer:
(c) glucose + fructose

Question 29.
Which enzyme is used in the conversion of sucrose into glucose and fructose?
(a) Zymase
(b) Invertase
(c) Diastase
(d) Maltase
Answer:
(b) Invertase

Question 30.
Which one of the following is the sweetest of all known sugars?
(a) Lactose
(b) Glucose
(c) Fructose
(d) Sucrose
Answer:
(c) Fructose

Question 31.
Which is the product formed when fructose undergoes partial reduction with sodium amalgam and water?
(a) Sorbital + mannitol
(b) D – mannose + D – galactose
(c) Gluconic acid + saccharic acid
(d) Aldehyde + ketone
Answer:
(a) Sorbital + mannitol

Question 32.
Which one of the following reagent is used to convert fructose into sorbitol and mannitol?
(a) LiAlH4
(b) Hl / Red P
(c) Na / Hg
(d) Conc. HNO3
Answer:
(c) Na / Hg

Question 33.
Fructose on oxidation with concentrated nitric acid gives
(a) glyceric acid + oxalic acid
(b) glycoffic acid + tartaric acid
(c) tartronic acid + mesoxalic acid
(d) acetic acid + hexanoic acid
Answer:
(b) glycoffic acid + tartaric acid

Question 34.
How many asymmetric carbon atoms are present in fructose?
(a) 4
(b) 3
(c) 2
(d) 6
Answer:
(b) 3

Question 35.
Two monosaccharides are linked by to form a disaccharide.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-14
Answer:
(a) glycosidic linkage

Question 36.
Which of the following is not an example of disaccharide?
(a) Sucrose
(b) Lactose
(c) Maltose
(d) Cellulose
Answer:
(d) Cellulose

Question 37.
The enzyme that catalyses the hydrolysis of sucrose to glucose and fructose is …………….
(a) zymase
(b) invertase
(c) diastase
(d) maltase
Answer:
(b) invertase

Question 38.
Which one of the following contains a mixture of glucose, fructose and sucrose?
(a) Sugarcane
(b) Bectroot
(c) Honey
(d) Mango
Answer:
(c) Honey

Question 39.
Consider the following statements
(i) in sucrose, C1 of a – D – glucose is joined to C2 of D – fructose.
(ii) Two monosaccharides are linked by glycosidic linkage.
(iii) In sucrose, C2 of a – D – glucose is joined to C1 of D – fructose.
Which of the above statement is / are correct?
(a) (iii) only
(b) (i) & (ii)
(c) (ii) only
(d) (i) & (iii)
Answer:
(b) (i) & (ii)

Question 40.
Which one of the following is an example of non – reducing sugar?
(a) Glucose
(b) Dextrose
(c) Lactose
(d) Sucrose
Answer:
(d) Sucrose

Question 41.
Which one of the following on hydrolysis give galactose and glucose?
(a) Maltose
(b) Cellulose
(c) Lactose
(d) Sucrose
Answer:
(c) Lactose

Question 42.
Which one of the following is called milk sugar?
(a) Lactose
(b) Glucose
(c) Sucrose
(d) Raffinose
Answer:
(a) Lactose

Question 43.
Which of the following is the major source of maltose?
(a) Honey
(b) Apple
(c) Sprouting barley
(d) Grapes
Answer:
(c) Sprouting barley

Question 44.
Which one is produced during digestion of starch by the enzyme α – amylase?
(a) Maltose
(b) Glucose
(c) Fructose
(d) Lactose
Answer:
(a) Maltose

Question 45.
Consider the following statements
(I) Maltose consists two molecules of α – D glucose units linked by an α – 1, 4 glycosidic bond.
(ii) Maltose act as non-reducing sugar.
(iii) Maltose is produced during digestion of cellulose by the enzyme a-amylase.
Which of the above statement is / are not correct?
(a) (i) only
(b) (i) & (iii)
(c) (iii) only
(d) (ii) & (iii)
Answer:
(d) (ii) & (iii)

Question 46.
Which one of the following is hetero polysaccharide?
(a) Starch
(b) Heparin
(c) Cellulose
(d) Glycogen
Answer:
(b) Heparin

Question 47.
Which one of the following is a homopolysaccharide?
(a) Hyaluronic acid
(b) Heparin
(c) Both (a) & (b)
(d) Starch
Answer:
(d) Starch

Question 48.
Consider the following statements
(I) Starch contains 80% of amylase and about 20% amylopectin.
(ii) Polysaccharides are called sugars.
(iii) Lactose act as a reducing agent.
Which of the above statement is / are not correct?
(a) (i) & (ii)
(b) (iii)
(c) (ii) & (iii)
(d) (ii) only
Answer:
(a) (i) & (ii)

Question 49.
Which one of the following gives blue colour with amylose and purple colour with amylopectin?
(a) Tollen’s reagent
(b) Fehling’s solution
(c) Iodine solution
(d) Bromic water
Answer:
(c) Iodine solution

Question 50.
Which colour is formed when amylose is treated with iodine solution?
(a) Purple
(b) Red
(c) Blue
(d) Violet
Answer:
(c) Blue

Question 51.
Which colour is formed when amylopectin is treated with iodine solution?
(a) Purple
(b) Blue
(c) Green
(d) Red
Answer:
(a) Purple

Question 52.
Which one of the following is the major constituent of plant cell walls?
(a) Starch
(b) Cellulose
(c) Glycogen
(d) Amylose
Answer:
(b) Cellulose

Question 53.
Consider the following statements
(i) Cellulose is a straight chain polysaccharide.
(ii) The glucose molecules in cellulose arc linked by β(1, 4) glycosidic bond.
(iii) Cotton is almost pure starch.
Which of the above statement is / are correct?
(a) (i) only
(b) (ii) only
(c) (iii) only
(d) (i) & (ii)
Answer:
(d) (i) & (ii)

Question 54.
Which of the following enzyme can hydrolyse the cellulose?
(a) Invertase
(b) Glycosidase
(c) Zymase
(d) Diastase
Answer:
(b) Glycosidase

Question 55.
Which one of the following is called gun cotton?
(a) Nitrated ester of cellulose
(b) Cellulose acetate
(c) Glyceryl trinitrate
(d) Trinitrotoluene
Answer:
(a) Nitrated ester of cellulose

Question 56.
Which one of the following is called animal starch?
(a) Cellulose
(b) Glycogen
(c) Lactose
(d) Fat
Answer:
(b) Glycogen

Question 57.
Consider the following statements
(i) The excessive glucose in the body is stored in the form of arnylose and amylopectin.
(ii) Glycogeri is present in the liver and muscle of animals.
(iii) Protein is stored in the body as glycogen and in plant as starch.
Which of the above statement is / are not correct?
(a) (¡) & (iii)
(b) (ii) & (iii)
(c) (i) only
(d) (iii) only
Answer:
(d) (iii) only

Question 58.
Which one of the following is stored in the body as glycogen and in plant as starch?
(a) Protein
(b) Vitamin
(c) Fat
(d) Carbohydrates
Answer:
(d) Carbohydrates

Question 59.
Which one of the following act as shock absorber and lubricant?
(a) Glycosamino glycans
(b) Glycogen
(c) Cellulose nitrate
(d) Rayon explosive
Answer:

Question 60.
Which biomolecule is the most abundant in all living organisms?
(a) Carbohydrates
(b) Vitamins
(c) Hormones
(d) Proteins
Answer:
(d) Proteins

Question 61.
Which of the following is mainly present in proteins?
(a) 3 – keto acid
(b) 1 – amino acid
(c) α, β – ketol
(d) amide and acids
Answer:
(b) 1 – amino acid

Question 62.
Which of the amino acid is optically inactive?
(a) Alanine
(b) Valine
(c) Glycine
(d) Proline
Answer:
(c) Glycine

Question 63.
Proteins are generally …………..
(a) poly amides
(b) polyesters
(c) polymer
(d) poly peptide
Answer:
(d) poly peptide

Question 64.
Which one of the following is an example for fibrous protein?
(a) Myoglobin
(b) Insulin
(c) Keratin
(d) Enzymes
Answer:
(c) Keratin

Question 65.
Which one of the following is an example for globular protein?
(a) Kerating
(b) Myoglobin
(c) Collagen
(d) Etastin
Answer:
(b) Myoglobin

Questin 66.
Consider the following statement
(i) The amino acids arc linked electro valently by peptide bonds in proteins.
(ii) Fibrous proteins are linear molecules similar to fibres.
(iii) Globular proteins have a linear shape.
Which of the above statement is / are not correct?
(a) (iii) only
(b) (i) & (iii)
(c) (ii) & (iii)
(d) (ii) only
Answer:
(b) (i) & (iii)

Question 67.
Consider the following statement
Answer:
(I) The relative arrangement of amino acids in the polypeptide chain called the secondary structure of protein.
(ii) α – Helix and β – strands are two most common sub structures formed by proteins.
(iii) α – Helix and β – strands further folds to form the three dimensional arrangement in tertiary structure of proteins.
Which of the above statement is / are correct?
(a) (i) only
(b) (ii) & (iii)
(c) (i) & (iii)
(d) (ii) only
Answer:
(b) (ii) & (iii)

Question 68.
Which of the following act as structural backbones?
(a) Keratine, collagen
(b) Myoglobin, insulin
(c) Glycine, proline
(d) Alanine, cysteine
Answer:
(a) Keratine, collagen

Question 69.
Which protein control the glucose level in the blood?
(a) Kerating, collagen
(b) Insulin, glucagon
(c) Glycine, proline
(d) Alanine, myoglobin
Answer:
(b) Insulin, glucagon

Question 70.
Which one of the following act as catalyst in the interconversion of carbonic acid to water and carbondioxide?
(a) Lactose
(b) Carbonic anhydrase
(c) Glycosidase
(d) Invertase
Answer:
(b) Carbonic anhydrase

Question 71.
Which enzyme catalyses the hydrolysis of sucrose to fructose and glucose?
(a) Lactase
(b) invertase
(c) Sucrase
(d) Zymase
Answer:
(c) Sucrase

Question 72.
Lactase enzyme hydrolyses the lactose into its constituent as …………..
(a) glucose, fructose
(b) glucose, galactose
(c) fructose only
(d) glucose only
Answer:
(b) glucose, galactose

Question 73.
Consider the following statement
(i) Lipids are the principal components of cell membranes including cell walls.
(ii) Enzymes are biocatalysts that catalyse a specific biochemical reaction.
(iii) Carbonic anhydrase enzyme catalyses the hydrolysis of sucrose to fructose and glucose.
Which of the above statement is / are correct?
(a) (i) only
(b) (iii) only
(c) (i) & (iii)
(d) (ii) & (iii)
Answer:
(c) (i) & (iii)

Question 74.
Which one help in the absorption and transport of fat soluble vitamins?
(a) Lipids
(b) Protein
(c) Enzyme
(d) Water
Answer:
(a) Lipids

Question 75.
Which one act as emulsifier in fat metabolism?
(a) Enzymes
(b) Fats
(c) Lipids
(d) Proteins
Answer:
(c) Lipids

Question 76.
Which one of the following is fat soluble vitamin?
(a) Vitamin B1
(b) Vitamin B6
(c) Vitamin C
(d) Vitamin A
Answer:
(d) Vitamin A

Question 77.
Which one of the following is a water soluble vitamin?
(a) Vitamin A
(b) Vitamin D
(c) Vitamin C
(d) Vitamin K
Answer:
(c) Vitamin C

Question 78.
Which one of the following deficient disease of Vitamin A?
(a) Cheilosis
(b) Xerophthalmia
(c) Convulsions
(d) Perncious Anaemia
Answer:
(b) Xerophthalmia

Question 79.
Which Vitamin deficiency leads to cheilosis?
(a) Vitamin B12
(b) Vitamin B6
(c) Vitamin B2
(d) Vitamin B5
Answer:
(c) Vitamin B2

Question 80.
Which one of the following vitamin deficiency leads to Rickets?
(a) Vitamin A
(b) Vitamin B1
(c) Vitamin C
(d) Vitamin D
Answer:
(d) Vitamin D

Question 81.
Which vitamin deficiency leads to Hair loss, muscle pain?
(a) Biotin
(b) Niacin
(c) Riboflavin
(d) Thiamine
Answer:
(a) Biotin

Question 82.
The deficiency of Vitamin B12 leads to the disease ………………..
(a) convulsions
(b) beriberi
(c) Pernicious anaemia
(d) pellagra
Answer:
(c) Pernicious anaemia

Question 83.
Which of the following is the chemical name of vitamin B12?
(a) Folic acid
(b) Cobalamin
(c) Pyridoxime
(d) Riboflavin
Answer:
(b) Cobalamin

Question 84.
Night blindness and kertinisation of skin is the chemical name of Vitamin B12?
(a) vitamin B1
(b) vitamin C
(c) vitamin A
(d) vitamin B12
Answer:
(c) vitamin A

Question 85.
Which vitamin deficiency leads to the disease megaloblastic anaemia?
(a) Vitamin B9
(b) Vitamin B6
(c) Vitamin B12
(d) Vitamin B2
Answer:
(a) Vitamin B9

Question 86.
Which one of the following is rich in liver oil, carrot, mango and papaya?
(a) Vitamin B1
(b) Vitamin C
(c) Vitamin A
(d) vitamin D
Answer:
(c) Vitamin A

Question 87.
Which of the vitamin deficiency leads to photosensitive dermatitis (or) pellagra?
(a) Vitamin B5
(b) Vitamin B6
(c) Vitamin B3
(d) Vitamin D
Answer:
(c) Vitamin B3

Question 88.
Depression, Hair loss, muscle pain are due to the deficiency of vitamin ……………..
(a) A
(b) B12
(c) B2
(d) B7
Answer:
(d) B7

Question 89.
The chemical name of vitamin B9 is …………….
(a) biotin
(b) folic acid
(c) niacin
(d) thiamin
Answer:
(b) folic acid

Question 90.
Which of the following is rich in citrus, fruits, tomato, amia and leafy vegetables?
(a) Vitamin C
(b) Vitamin E
(c) Vitamin A
(d) Vitamin D
Answer:
(a) Vitamin C

Question 91.
Consider the following statement
(i) Vitamin D functions in the adsorption and maintenance of calcium.
(ii) Vitamin E act as an antioxidant.
(iii) Vitamin C functions in blood clotting.
Which of the above statement is / are correct?
(a) (iii) only
(b) (ii) & (iii)
(c) (i) & (ii)
(d) (i) only
Answer:
(c) (i) & (ii)

Question 92.
Which vitamin is rich in cotton seed oil, sunflower oil, wheat germ oil and all vegetable oils?
(a) Vitamin C
(b) Vitamin E
(c) Vitamin A
(d) Vitamin D
Answer:
(b) Vitamin E

Question 93.
Which vitamin deficiency leads to the disease osteomalacia?
(a) Vitamin D
(b) Vitamin A
(c) Vitamin C
(d) Vitamin K
Answer:
(a) Vitamin D

Question 94.
Which one of the following is mainly required for blood clotting?
(a) Vitamin E
(b) Vitamin B12
(c) Vitamin C
(d) Vitamin K
Answer:
(d) Vitamin K

Question 95.
Consider the following statement
(i) Nucleic acid are biopolymers of nucleotides.
(ii) Controlled hydrolysis of DNA and RNA yield 3 components namely a nitrogeneous base, a pentose sugar and sulphate group.
(iii) DNA and RNA are the molecular repositories that carry genetic information in every organism.
Which of the above statement is / are correct?
(a) (i) only
(b) (ii) only
(c) (i) & (iii)
(d) (ii) & (iii)
Answer:
(c) (i) & (iii)

Question 96.
Which one of the following is found in cytoplasm and in nbosomers which contain 60% RNA and 40% protein.
(a) Ribosomal RNA
(b) Messenger RNA
(c) Transfer RNA
(d) DNA
Answer:
(a) Ribosomal RNA

Question 97.
Consider the following statement .
(i) Ribosomes are the sites at which protein synthesis takes place.
(ii) Messenger RNA carried genetic information from DNA to the ribosomes for protein synthesis.
(iii) t RNA consist of 20 – 40 nucleotides in a single chain.
Which of the above statement is / are not correct?
(a) (i) only
(b) (i) & (ii)
(c) (iii) only
(d) (ii) & (iii)
Answer:
(c) (iii) only

Question 98.
What is the name of the process of synthesis of mRNA from DNA strand?
(a) Transpiration
(b) Transcription
(c) Transformation
(d) Trans esterification
Answer:
(b) Transcription

Question 99.
Consider the following statement
(i) DNA mainly present in cytoplasm, nucleolus and ribosomes.
(ii) RNA is stable and not hydrolysed easily by alkalis.
(iii) DNA can replicate itself.
Which of the above statement is / are correct?
(a) (iii) only
(b) (i) only
(c) (i) & (ii)
(d) (ii) & (iii)
Answer:
(c) (i) & (ii)

Questin 100.
Who invented DNA finger printing?
(a) Sir Alec Jeffrey
(b) Rosalind Franklin
(c) Watson and Crick
(d) Maurice Wilkins
Answer:
(a) Sir Alec Jeffrey

Question 101.
Which one of the following can act as energy carriers?
(a) GTN
(b) ATP
(c) FAD
(d) Cyclic AMP
Answer:
(b) ATP

Questin 102.
Adenosine 3’, 5’- cyclic monophosphate a chemical messenger is otherwise called …………….
(a) ATP
(b) cyclic ADP
(c) cyclic AMP
(d) 3’P – ADP
Answer:
(c) cyclic AMP

Question 103.
Consider the following statement
(i) Endocrine glands make hormones.
(ii) Hormones may be classified as either protein (or) steroids
(iii) Hormones are intracellular signalling molecule.
Which of the above statement is / are not correct?
(a) (i) only
(b) (ii) & (iii)
(c) (iii) only
(d) (i) & (iii)
Answer:
(c) (iii) only

Question 104.
Which one of the following is a steroid?
(a) Insulin
(b) Epinephrine
(c) mutin
(d) Estrogen
Answer:
(d) Estrogen

Question 105.
Which one of the following is a protein hormone?
(a) Insulin
(b) Androgen
(c) Cortisol
(d) Estrogen
Answer:
(a) Insulin

Question 106.
The nucleic acid base having two possible binding sites is …………….
(a) thymine
(b) cytosine
(c) guanine
(d) adenine
Answer:
(c) guanine

Question 107.
DNA multiplication is called ………….
(a) transcription
(b) transformation
(c) transduction
(d) replication
Answer:
(d) replication

Question 108.
Insulin is a protein which plays the role of ……………
(a) an antibody
(b) a hormone
(c) an enzyme
(d) a transporting agent
Answer:
(b) a hormone

Question 109.
Which metal is present in Vitamin B12?
(a) Ca (II)
(b) Zn (II)
(c) Fe (II)
(d) Co (III)
Answer:
(d) Co (III)

Question 110.
The helical structure of protein is stablized by ………………
(a) oxygen bonds
(b) peptide bonds
(c) dipeptide bonds
(d) hydrogen bonds
Answer:
(d) hydrogen bonds

Question 111.
The cell membranes are mainly composed of ………….
(a) carbohydrates
(b) proteins
(c) phospholipids
(d) fats
Answer:
(c) phospholipids

Question 112.
Which one of the following is a polysaccharide?
(a) Nylon
(b) Amylose
(c) Ribose
(d) Polyethene
Answer:
(b) Amylose

Question 113.
Ribose ¡san example of …………….
(a) keto hexose
(b) aldohexose
(c) aldo pentose
(d) disaccharide
Answer:
(c) aldo pentose

Question 114.
Sucrose molecule is made up of …………..
(a) a gluco pyranose and fructo pyranose
(b) a glyco pyranose and fructo furanose
(c) a gluco furanose and fructo pyranose
(d) a gluco furanose and fructo furanose
Answer:
(b) a glyco pyranose and fructo furanose

Question 115.
A nucleotide consists of ……………….
(a) base and sugar
(b) base and phosphate
(c) sugar and phosphate
(d) base, sugar and phosphate
Answer:
(d) base, sugar and phosphate

Question 116.
Which of the following is responsible for heredity character?
(a) DNA
(b) RNA
(c) Proteins
(d) Hormones
Answer:
(a) DNA

Question 117.
The base adenine present in …………….
(a) DNA only
(b) RNA only
(c) Both DNA & RNA
(d) Protein
Answer:
(c) Both DNA & RNA

Question 118.
The protein which maintains the blood sugar level in the human body is …………..
(a) haemoglobin
(b) oxytocin
(c) insulin
(d) ptyalin
Answer:
(c) insulin

Question 119.
Ascorbic acid is a …………
(a) vitamin
(b) enzyme
(c) protein
(d) hormone
Answer:
(a) vitamin

Question 120.
Which of the following is not a constitutent of RNA?
(a) Ribose
(b) Phosphate
(c) Adenine
(d) Pyridine
Answer:
(d) Pyridine

Question 121.
Which one is fouñd in ATP ribonucleotide?
(a) Guanine
(b) Uracil
(c) Adenine
(d) Inulin
Answer:
(c) Adenine

Question 122.
Which substance is not present in nucleic acid?
(a) Cytosine
(b) Adenine
(c) Thymine
(d) Guanidine
Answer:
(d) Guanidine

Question 123.
In nucleic acid, the correct sequence is ……………..
(a) base – phosphate sugar
(b) phosphate – base – sugar
(c) sugar – base – phosphate
(d) base – sugar – phosphate
Answer:
(d) base – sugar – phosphate

Question 124.
The double helical structure of DNA was proposed by ……………….
(a) Watson and Crick
(b) Meicher
(c) Emil Fischer
(d) Khorana
Answer:
(a) Watson and Crick

Question 125.
Which substance is not present in nucleic acid?
(a) Cytosine
(b) Adenine
(c) Thymine
(d) Guanidine
Answer:
(d) Guanidine

Question 126.
In DNA, the complementary bases are ……………….
(a) Uracil and adenine; cytosine and guanine
(b) Adenine and thymine; guanine and cytosine
(c) Adenine and guanine; thymine and cytosine
(d) adenine and guanine; thymine and uracil
Answer:
(b) Adenine and thymine; guanine and cytosine

Question 127.
The structure of DNA is …………….
(a) linear
(b) single helix
(c) double helix
(d) triple helix
Answer:
(c) double helix

Question 128.
A gene is a segment of molecule of ……………
(a) DNA
(b) m – RNA
(c) t – RNA
(d) protein
Answer:
(a) DNA

Question 129.
The deficiency of vitamin C causes …………….
(a) scurvy
(b) rickets
(c) pyrrohea
(d) pellagra
Answer:
(a) scurvy

Question 130.
Which sugar is present in DNA?
(a) Deoxyribose
(b) Ribose
(c) D – fructose
(d) D – glucose
Answer:
(a) Deoxyribose

Question 131.
The base present ¡n DNA but not in RNA is …………..
(a) guanne
(b) adenine
(c) uracil
(d) thymine
Answer:
(d) thymine

Question 132.
Mutation of DNA occurs due to changes in the sequence of one of the following.
(a) Bases
(b) Ribose units
(c) Phosphate units
(d) Sugar units
Answer:
(a) Bases

Question 133.
Blood calcium level can be increased by the administration of ……………….
(a) glucogon
(b) calcitonin
(c) thyroxine
(d) paratharmone
Answer:
(d) paratharmone

Question 134.
The first hormone chemically synthesised in the laboratory is …………….
(a) cortisone
(b) insulin
(c) adrenaline
(d) eastrone.
Answer:
(b) insulin

Question 135.
RNA is different from DNA because RNA contains ……………
(a) Ribose sugar and tymine
(b) Ribose sugar and uracil
(c) Doxyribose sugar and thymine
(d) Deoxy ribose sugar and uracil
Answer:
(b) Ribose sugar and uracil

Question 136.
The hormone that helps in the conversion of glucose to glycogen is ……………..
(a) adrenaline
(b) insulin
(c) cortisone
(d) bile acid
Answer:
(b) insulin

Question 137.
Enery is stored in our body in the form of ………….
(a) ATP
(b) ADP
(c) Fats
(d) carbohydrates
Answer:
(a) ATP

Question 138.
Nucleic acid is a polymer of …………….
(a) Nucleosides
(b) a – aminoacids
(c) nucleotides
(d) glucose
Answer:
(c) nucleotides

Question 139.
Which one of the following is named as peptides?
(a) Esters
(b) Salts
(c) Amides
(d) Ketones
Answer:
(c) Amides

Question 140.
Irreversible precipitation of proteins is called ……………
(a) denaturation
(b) hydrolysis
(c) transformation
(d) trans esterification
Answer:
(a) denaturation

Question 141.
Which of the following is not an essential amino acid?
(a) Valine
(b) Lysinc
(c) Histidine
(d) Glycine
Answer:
(d) Glycine

Question 142.
Proteins are hydrolysed by enzymes into …………….
(a) dicarboxylic acid
(b) hydroxy acids
(c) amino acids
(d) aromatic acids
Answer:
(c) amino acids

Question 143.
Which one of the protein transports oxygen in the blood stream?
(a) Myoglobin
(b) Insulin
(c) Albumin
(d) Haemoglobin
Answer:
(d) Haemoglobin

Question 144.
Enzymes in the living systems …………..
(a) provide energy
(b) provide immunity
(c) catalyse biological process
(d) transport oxygen
Answer:
(c) catalyse biological process

Question 145.
Which compound can exist in a dipolar state?
(a) C6H5 CH2 CH (N = CH2) COOH
(b) (CH3)2 CH – CH (NH2) COOH
(c) C6H5CONH CH2 COOH
(d) HOOC – CH2 – CH2 – CO – COOH
Answer:
(b) (CH3)2 CH – CH (NH2) COOH

Question 146.
Haemoglobin is …………….
(a) an enzyme
(b) a globular protein
(c) a vitamin
(d) carbohydrate
Answer:
(b) a globular protein

Question 147.
The number of essential amino acid in man is …………….
(a) 8
(b) 10
(c) 20
(d) 18
Answer:
(b) 10

Question 148.
Which one of the biomolecule is insoluble in water?
(a) Keratin
(b) Haemoglobin
(c) Ribonuclease
(d) Aclenine
Answer:
(a) Keratin

Question 149.
Which of the following is used in our body as a fuel for muscles and nerves and to build and repair body tissues?
(a Cane sugar
(b) Fructose
(c) Proteins
(d) Glucose
Answer:
(c) Proteins

Question 150.
The bond that determines the secondary structure of proteins is …………..
(a) coordinate bond
(b) covalent bond
(c) hydrogen bond
(d) peptide bond
Answer:
(c) hydrogen bond

Question 151.
Which of the following monosaccharide is a pentose?
(a) Galactose
(b) Glucose
(c) Fructose
(d) Arabinose
Answer:
(d) Arabinose

Question 152.
Which of the following is a carbohydrate?
(a) Leucine
(b) Albumin
(c) Inulin
(d) Maltase
Answer:
(c) Inulin

Question 153.
Glucose gives silver mirror with Tollens reagent. it shows the presence of ……………..
(a) an acidic group
(b) an alcoholic group
(c) a ketonic group
(d) an aldehydic group
Answer:
(d) an aldehydic group

Question 154.
The compound which does not contain an asymmetric carbon atom is …………….
(a) glyceraldehyde
(b) glycine
(c) glucose
(d) fructose
Answer:
(b) glycine

Question 155.
Which one of the following compounds is found abundantly in nature?
(a) Fructose
(b) Starch
(c) Glucose
(d) Cellulose
Answer:
(d) Cellulose

Question 156.
Blood sugar is the same as ……………
(a) glucose
(b) galactose
(c) glycogen
(d) fructose
Answer:
(a) glucose

Question 157.
Which of the following is an aldohexose?
(a) Sucrose
(b) Cellulose
(c) Glucose
(d) Raffinose
Answer:
(c) Glucose

Question 158.
Glucose and mannose are …………..
(a) epimers
(b) anomers
(c) keto hexoses
(d) disaccharides
Answer:
(a) epimers

Question 159.
Which of the following is the sweetest sugar?
(a) Glucose
(b) Fructose
(c) Lactose
(d) Sucrose
Answer:
(b) Fructose

Question 160.
In fructose, the possible optical isomers are …………..
(a) 12
(b) 16
(c) 8
(d) 4
Answer:
(c) 8

Question 161.
Which one of the following is not used to convert glucose into gluconic acid?
(a) Br2 water
(b) Cone. HNO3
(c) Tollen’s reagent
(d) Fehling’s solution.
Answer:
(b) Cone. HNO3

II. Fill in the blanks.

  1. Chemically, carbohydrates are defined as …………. or …………. with a general formula
  2. …………. are synthesised by green leaves during photo synthesis.
  3. Almost all …………. are optically active as they have one or more chiral carbon.
  4. …………. are carbohydrates that cannot be hydrolysed further and are also called simple sugars.
  5. Erythrose is an example of ………….
  6. Glyceraldehyde is an example of …………. in monosaccharides.
  7. Glucose in human blood about …………. and it also known as ………….
  8. Ribulose is an example of ………….
  9. Glucose solution is optically active and it rotates the plane polarised light in …………. direction and so it called
  10. Glucose when oxidised with con.HNO3 gives ………….
  11. The reaction of glucose with Tollents reagent or Fehlmg’s solution confirms the presence of …………. group in glucose.
  12. The exact special arrangement of – OH groups in glucose was given by ………….
  13. The two isomers differ only in the configuration of C1 carbon are called ………….
  14. The cyclic structure of glucose with 5 carbon and one oxygen atom is called ………….
  15. The slow interconversion of α – D glucose and β – D glucose via open chain form under equilibrium is called ………….
  16. Sugars differing in configuration at an asymmetric centre is known as ………….
  17. …………. is present abundantly in fruts and hence it is also called fruit sugar.
  18. The solution having equal amount of glucose and fructose is termed as ………….
  19. Partial reduction of fructose with sodium amalgam and water produces …………. and …………. which are at second carbon.
  20. The reaction sodium amalgam and water with fructose confirms the presence of ………….
  21. The cyclic form of fructose is called ………….
  22. Disaccharides have general formula ………….
  23. In disaccharides, two monosaccharides are linked by …………. called ………….
  24. …………. is primary mixture of glucose, fructose and sucrose.
  25. Sucrose is also called …………. sugar.
  26. …………. is produced during digestion of starch by the enzyme a-amylase
  27. Starch contains about 20% …………. and about 80% of .
  28. Starch is used for …………. in plants.
  29. Cotton is almost pure ………….
  30. …………. is the storage polysaccharides of animals.
  31. …………. act as shock absorber and lubricant
  32. Proteins are polymers of ………….
  33. Orinithine and citrulline are called ………….
  34. At a specific pH value the net charge of an amino acid in neutral is called ………….
  35. Except …………. all other amino acids are optically active.
  36. In proteins, the amino acids are linked covalently by ………….
  37. The process of a protein, losing its higher order structure without losing the primary structure is called ………….
  38. Proteins such as …………. , …………. act as structural back bones.
  39. …………. and …………. controls the glucose level in the blood.
  40. …………. are biocatalysts that catalyse a specific biochemical reaction.
  41. …………. act as protective coating in aquatic organisms.
  42. Lipids act as …………. in fat metabolism.
  43. …………. help in the absorption and transport of fat soluble vitamins.
  44. Vitamin A, D, E and K …………. are vitamins.
  45. The chemical name of Vitamin A is ………….
  46. …………. deficiency leads to the disease cheilosis.
  47. …………. deficiency leads to the disease pellagra.
  48. …………. is a part of coenzyme A in carbohydrate protein and fat metabolism.
  49. …………. is rich in mushroom, avocada, egg yolk, sunflower oil.
  50. …………. deficiency leads to pernicious Anaemia.
  51. All citrus fruits and amla are rich in vitamin ………….
  52. …………. functions in blood clotting.
  53. Nucleic acids are bio polymers of ………….
  54. Both DNA and RNA have two major purine bases …………. and ………….
  55. The recurring deoxyribonucleotie units of DNA contains …………. and the ribonucleotide units of RNA contain
  56. The molecule with the phosphate group is called a ………….
  57.  The specific association of the two chains of the double helix in DNA is known as ………….
  58. t RNA molecule consists of …………. nucleotides in a single chain
  59. The synthesis of mRNA from DNA strand is called ………….
  60. …………. carries genetic information from DNA to the ribosomes for protein synthesis.
  61. …………. was first invented by Sir Alec Jeifry.

Answer:

  1. polyhydroxy aldehydes, ketoses, C(H2O)
  2. Carbohydrates
  3. carbohydrates
  4. Monosaccharides
  5. monosaccharide
  6. aldotriose
  7. 100 mg/dI, blood sugar
  8. ketopentose
  9. clockwise, dextrose
  10. glucaric acid (or) saccharic acid
  11. aldehyde
  12. Emil Fischer
  13. anomers
  14. pyranose form
  15. mutarotation
  16. epimers
  17. fructose
  18. invert sugar
  19. sorbitol, mannitol, epimers
  20. keto group
  21. furanose form
  22. Cn(H2O)n-1
  23. oxide, linkage, glycosidic linkage
  24. honey.
  25. invert (or) non reducing
  26. maltose
  27. amylose, amylopectin
  28. energy storage
  29. cellulose
  30. glycogen
  31. hyaluronate (or) glycosaminoglycans
  32. α – amino acids
  33. non – protein amino acids
  34.  iso electric point
  35. glycine
  36. peptide bonds
  37. denaturation
  38. keratin, collagen
  39. Insulin, glucagon
  40. Enzymes
  41. Lipids
  42. emulsifier
  43. Lipids
  44. fact – soluble
  45. retinol
  46. Vitamin B2
  47. Vitamin B3
  48. Vitamin B5
  49. Vitamin B5
  50. Vitamin B12
  51. C
  52. Vitamin K
  53. nucleotides
  54. adenine, guanine
  55.  2’ – doxy – D -ribose, D-ribose
  56.  nucleoside
  57. complementary base pairing
  58. 73 -94
  59. transcription
  60. mRNA
  61. DNA finger printing.

III. Match the column I and Column II using the code given below the column.

Question 1.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-15
Answer:
(a) 4 3 2 1

Question 2.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-16
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-17
Answer:
(b) 2 1 4 3

Question 3.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-18
Answer:
(a) 3 1 4 2

Question 4.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-19
Answer:
(d) 2 3 4 1

Question 5.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-20
Answer:
(a) 3 4 2 1

Question 6.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-21
Answer:
(d) 2 3 4 1

Question 7.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-22
Answer:
(a) 3 4 1 2

Question 8.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-23
Answer:
(a) 3 1 4 2

Question 9.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-24
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-25
Answer:
(a) 3 4 1 2

Question 10.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-26
Answer:
(a) 3 4 1 2

Question 11.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-27
Answer:
(a) 2 4 1 3

Question 12.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-28
Answer:
(a) 2 3 4 1

IV. Assertion and reasons.

Question 1.
Assertlon(A): Almost all carbohydrates are optically active.
Reason (R): All carbohydrates have one or more chiral carbon atoms.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not the correct explanation of A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 2.
Assertion(A): Glucose is called blood sugar.
Reason (R): Human blood contains about 100 mg/di of glucose hence it is called blood sugar.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not the correct explanation of A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R ¡s the correct explanation of A.

Question 3.
Assertlon(A): Glucose is called aldohexose as well as dextrose.
Reason (R): Glucose contain an aldehyde group and it rotates the plane polarised light in the clockwise direction.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not the correct explanation of A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 4.
Assertion(A): Glucose contains an aldehyde group and it occupies one end of the carbon chain.
Reason (R): When glucose is oxidised by bromine water, it gets oxidised to gluconic acid confirms the position of aldehyde group.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not the correct explanation of A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 5.
Assertion(A): Glucose contains one primary alcohol group at the end of the carbon chain.
Reason (R): When glucose is oxidised by strong oxidising agent conc.HNO3 it gives glucaric acid proves the presence of- CH2OH group at one end of carbon chain in glucose.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not the correct explanation of A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 6.
Assertion(A): Glucose and mannose are epimers.
Reason (R): Sugars differing in configuration at an asymmetric centre are called epimers.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not the correct explanation of A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 7.
Assertion(A): Fructose is called levulose and keto hexose
Reason (R): Fructose contains a ketone group and fructose rotates the plane polarised light in anic1ockwise direction.
(a) Both A and R are wrong
(b) Both A and R are correct and R is the correct explanation of A.
(c) A is wrong but R is correct.
(d) A is correct hut R is wrong.
Answer:
(b) Both A and R are correct and R is the correct explanation of A.

Question 8.
Assertion(A): Sucrose is called invert sugar.
Reason (R): During hydrolysis of sucrose, the optical rotation of the reaction mixture changes from dextro to levo.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not the correct explanation of A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 9.
Assertion(A): Sucrose is a non reducing sugar.
Reason (R): in sucrose. C1 of α – D glucose and C2 of D-fructose are joined together by glycosidic bond. Both the carbonyl carbons are involved in glycosidic bonding.
(a) Both A and R are correct but R is not the correct explanation of A.
(b) Both A and R are correct and R the correct explanation of A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(b) Both A and R are correct and R the correct explanation of A.

Question 10.
Assertion(A): A disaccharide lactose act as reducing sugar.
Reason (R): In lactose, β – D galactose and β – D glucose are linked by β – 1, 4 – glycosidic bond in which aldehyde group is not involved.
(a) A is correct but R is wrong.
(b) Both A and R are correct but R is not the correct explanation of A.
(c) Both A and R are correct and R is the correct explanation of A.
(d) A is wrong but R is correct.
Answer:
(c) Both A and R are correct and R is the correct explanation of A.

Question 11.
Assertion(A): Lactose is referred to as milk sugar.
Reason (R): It is extracted from sprouted barley.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are worng.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(c) A is correct but R is wrong.

Question 12.
Assertion(A): Maltose, a disaccharide acts as a reducing sugar.
Reason (R): Maltose consists of two molecules of α – D glucose with linked by α, 1, 4 – glycosidic bond and one glucose has the carbonyl group.
(a) Both A and R are correct and R ¡s the correct explanation of A.
(b) Both A and R are correct but R is not the correct explanation of A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 13.
Assertion(A): Except glycine all other amino acids are optically active.
Reason (R): Glycine does not contain chira! carbon atom whereas in all other amino acids have chiral carbon atom.
(a) Both A and R are wrong.
(b) A is correct but R is wrong
(c) Both A and R are correct and R is the correct explanation of A.
(d) Both A and R are correct but R is not the correct explantion of A.
Answer:
(c) Both A and R are correct and R is the correct explanation of A.

Question 14.
Assertion(A): Enzymes have active sites and substrates, reactive sites on their surfaces respectively.
Reason (R): Active and reactive sites push the enzyme and substrate molecules away from each other.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not the correct explanation of A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 15.
Assertion(A): Enzymes are defined as biological proteins.
Reason (R): Chemically all enzymes are globular proteins.
(a) Both A and R are correct and R ¡s the correct explanation of A.
(b) Both A and R are wrong.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R ¡s the correct explanation of A.

Question 16.
Assertion(A): DNA and RNA molecules are found in the molecules of the cell.
Reason (R): On heating, enzymes do not lose their specific activity.
(a) Both A and R are correct and R explains A.
(b) Both A and R are wrong.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(b) Both A and R are wrong.

Question 17.
Assertion(A): Vitamin D can be stored in our body.
Reason (R): Vitamin D is a fat soluble vitamin.
(a) A is correct but R not explains A.
(b) Both A and R are correct and R explains A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(b) Both A and R are correct and R explains A.

Question 18.
Assertion(A): Glycine must be taken through diet.
Reason (R): It is an essential amino acid.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explain A.
(c) A is wrong but R is correct.
(d) Both A and R are wrong.
Answer:
(d) Both A and R are wrong.

Question 19.
Assertion(A): In proteins, amino acids are linked through peptide bonds.
Reason (R): Peptide bonds are glycosidic (or) oxygen bridges.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explains A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(c) A is correct but R is wrong.

Question 20.
Assertion(A): Monosaccharides are held by glycocidic bonds.
Reason (R): Monosaccharides are macro molecules.
(a) Both A and R are correct and R explains A.
(b) Both A and R are correct but R does not explains A.
(c) A is wrong but R is correct.
(d) Both A and R are wrong.
Answer:
(d) Both A and R are wrong.

V. Find the odd one out and give the reasons.

Question 1.
Glucose, fructose, galactose, mannose, sucrose.
Answer:
Sucrose, It is a disaccharide whereas other are monosaccharides.

Question 2.
Glucose, aldo hexose, dextrose, blood sugar, fruit sugar.
Answer:
Fruit sugar, It is the name of fructose, All others are indicating glucose only.

Question 3.
Fructose, fruit sugar, milk sugar, levulose, ketohexose.
Answer:
Milk sugar, It is the name of lactose, All others are indicating fructose only.

Question 4.
Mannose, sucrose, lactose, maltose, diastose.
Answer:
Mannose, It is a monosaccharide whereas otheres are disaccharide.

Question 5.
Keratm, glucose, mannose, starch, cellulose.
Answer:
Keratin, It is a protein whereas others are carbohydrates.

Question 6.
Keram, collagen, glycine, alanine, inulin, instilin.
Answer:
Inulin, It is a carbohydrates whereas others arc proteins.

Question 7.
Glycine, alanine, histidine, cultamine, proline, serine.
Answer:
Histidine. it is an essential amino acid whereas others are non essentîal amino acids.

Question 8.
Valine, phenyl alanine, histidine, lysine, alanine.
Answer:
Alanine, It is non essential amino acid whereas others are essential amino acids.

Question 9.
Invertase, maltase, zymase, maltose, lactase.
Answer:
Maltose, It is a carbohydrates whereas others are enzymes.

Question 10.
Vitamin A, Vitamin D, Vitamin C, Vitamin E, Vitamin K.
Answer:
Vitamin C is water soluble vitamins whereas others are fat soluble vitamins.

Samacheer Kalvi 12th Chemistry Biomolecules 2 Mark Questions and Answers

VI. Answer the following.

Question 1.
Define carbohydrates. Give example.
Answer:

  1. Carbohydrates are defined as polyhydroxy aldehydes (or) ketoses with a general formula Cn(H2O)n.
  2. They are considered as hydrates of carbon containing hydrogen and oxygen in the same ratio as in water.
  3. Example: Glucose, sucrose, cellulose.

Question 2.
Draw the structure of

  1. D – Glucose
  2. D – Fructose.

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-29

Question 3.
Draw the structure of sucrose
Answer:
Sucrose C12H22O11 is a disaccharide
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-30

Question 4.
Explain photosynthesis.
Answer:
Carbohydrates are synthesised by green leaves during photosynthesis, a complex process in which sunlight provides the energy to convert carbon dioxide and water into glucose and oxygen. Glucose is then converted into other carbohydrates and is consumed by animals.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-31

Question 5.
Draw and explain the structure of glyceraldehyde.
Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-32

2. D – Glyceraldehyde and L – Glyceraldehyde are two enantiomers.

3. D (or) (+) is dextre rotatory and L (or) (-) is levo rotatory.

Question 6.
What is meant by dextro and levo rotatory?
Answer:
1. Fischer has devise a projection formula to reláte the two enantiomeric forms. Base on this, carbohydrates are named as D or L.

2. + and – sign indicates the dextro rotatory and levo rotatory respectively.

3. Dextre rotatory compound rotate the plane of plane polarised light in clockwise direction while the levo rotatory compounds rotate in anticlockwise direction.

4. Dextro rotatory compounds are represented as D (+) or L (+) and the levo rotatiory compounds as D (-) or L (-).
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-33

Question 7.
Give examples for the following.

  1. Aldotriose
  2. Ketotriose
  3. Aldotetrose
  4. Ketotetrose

Answer:

  1. Aldotriose – Glyceraldehyde
  2. Ketotriose – Dihydroxy acetone
  3. Aldotetrose – Erythrose
  4. Ketotetrose – Erythrulose

Question 8.
Give examples for the following.

  1. Aldo pentose
  2. Keto pentose
  3. Aldo hexose
  4. Ketohexose

Answer:

  1. Aldo pentose – Ribose
  2. Keto pentose – Ribulose
  3. Aldo hexose – Glucose
  4. Keto hexose – Fructose

Question 9.
Explain the action of Conc.HNO3 with fructose with equation.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-34

Question 10.
Write a note about glycogen?
Answer:
1. Glycogcn is the storage polysaccharide of animals. It is present in the liver and muscles of animals. Glycogen is called as animal starch.

2. Glycogen on hydrolysis gives glucose molecules. Structurally glycogen resembles amylo pectin with more branching. In glycogen the branching occurs every 8 – 14 glucose units opposed to 24 – 30 units in amylopectin. The excessive glucose in the body is stored in the form of glycogen.

Question 11.
What are amino acid? Give its structure.
Answer:
1. Amino acids are compounds which contain an amino group and a carboxylic group. Protein molecules are made up of α, β, γ – amino acids.

2. The protein molecules are mde up of a-amino acids which can be represented by the following general formula.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-35

3. There are 20 amino acids commonly found in protein molecules.

Question 12.
Define iso electric point.
Answer:
At a specific pH value, the net charge of an amino acid in neutral is called iso electric point. At a pH value above the iso electric point the amino acid will be negatively charged and positively charged at pH values below the iso electric point.

Question 13.
Whatis zwitter ion? Give its structure.
Answer:
1. At aqueous solution, the proton from cabroxyl group can be transferred to the amino group of an amino acid leaving these groups with opposite charges.

2. Despite having both positive and negative charges, this molecule is neutral and has amphotenc behaviour. These ions are called zwitter ions.

3. Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-36

Question 14.
What are hormones? Mention their functions. Name some hormones.
Answer:
1. Hormones are organic compounds (eg. peptide or a steroid) that is secreted by endocrine glands. It is an inter cellular signalling molecule and induces a physiological response. Hormones maintain blood pressure, blood volume and electrolyte balance, embryogenesis, hunger, eating behaviour and digestion.

2. The major endogrine glands are the pituitary, pineal, thymus. thyroid, adrenal glands and pancreas. In addition men produces hormones in their testes and women produces hormones in their ovary.

Question 15.
What are the expected products of hyrolysis of lactose?
Answer:
Since lactose is a disaccharide, therefore on hydrolysis it gives two molecules of monosaccharides, i.e., one molecule each of D – (+) – glucose and D – (+) – galactose
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-37

Question 16.
Glucose or sucrose are soluble in water by cyclohexane or benzene (simple six membered ring compounds) are insoluble in water. Explain.
Answer:
Glucose and sucrose molecules contain many – OH groups and hence are capable of forming H – bond with water molecules. On the other hand, cyclohexane and benzene are hydrocarbon and hence they cannot form H-bond with water. Therefore, glucose and sucrose are soluble in water whereas cyclohexane and benzene are insoluble in water.

Question 17.
How do you explain the absence of aldehyde group in the pentaacetate of D – glucose?
Answer:
Since pentaacetate of D – glucose are not oxidised either by Tollen’s reagent or Fehling’s solution. This indicates the absence of aldehyde group.

Question 18.
Why cannot Vitamin C be stored in our body?
Answer:
Vitamin C is water soluble, therefore it is readily excreted in urine and hence cannot be stored in the body.

Question 19.
What do you understand by the term glycosidic linkage?
Answer:
In disaccharides or polysaccharides, monosaccharides are joined together by an oxide linkage formed by loss of a water molecule. Such a linkage between two monosaccaride units through oxygen atom is called glycosidic linkage.

Question 20.
What are essential and non-essential amino acids? Give two examples of each type.
Answer:
Essential amino acids:
Amino acids which cannot be synthesised in the body and must be obtained through regular diet are known as esential amino acids. Foe example: Valine, Leucine.

Non – essential amino acids:
The amino acids which can be synthesised in the body by itself are known as non – essential amino acids. For example: glycine, alanine.

Question 21.
What is the effect of denaturaion on the structure of proteins?
Answer:
During the denaturation process, 2° and 3° structure of proteins are destroyed by 1° structure remains intact. For example: curdling of milk.

Question 22.
How are vitamins classified? Name the vitamin responsible for the coagulation of blood.
Answer:
Vitamins are classified into two groups depending upon their solubility in water or fat.
1. Water soluble vitamins:
These include vitamins of ‘B’ group (except B12) and vitamin ‘C’.

2. Fat soluble vitamin:
These include vitamins A, D, E and K. They are stored in liver and adipose tissues. Vitamin ‘K’ is responsible for the coagulation of blood.

Question 23.
What are nucleic acids? Mention their two important functions.
Answer:
Nucleic acids are polymers of nucleotides containing a pentose sugar, heterocyclic base and a phosphate group. They help in synthesis of proteins. They are also responsible for the transfer of genetic characters from one generation to the next generation.

Question 24.
What is the difference between a nucleoside and a nucleotide?
Answer:
Nucleoside is formed by the condensation of a purine or pyrimidine base with pentose sugar at position 1. When nucleoside is linked to phosphoric acid at 5 position of sugar moiety, we get a nucleotide. Hence a nucleotide has three units – Phosphate group, pentose sugar and a base, whereas nucleoside has two units – pentose sugar and a base.

Question 25.
Write two main functions of carbohydrates in plants.
Answer:
Main functions of carbohydrates in plants:

  1. Carbohydrates are used as storage molecules as starch in plants.
  2. Cell wall of bacteria and plants is made up of cellulose.

Question 26.
Name two components of starch. How do they differ from each other structurally?
Answer:
The two components of starch are:

  1. Amylose
  2. Amylopectin

Amylose is a straight chain polymer of α – D – (+) glucose, while amylopectin is a branched chain polymer of α – D – glucose.

Question 27.
Name the four bases present in DNA. Which one of these is not present in RNA?
Answer:
DNA contains four bases, viz; adenine (A), guanine (G), cytosine (C), thymine (T). RNA also contain four bases, first three bases are same as in DNA but the fourth one is uracil(U).

Question 28.
Name two fat soluble vitamins, their sources and the diseases caused due to their deficiency in diet.
Answer:

Vitamins

  1. Vitamin A
  2. Vitamin D

Sources

  1. Fish, liver oil, carrot
  2. Sunlight, milk, egg yolk

Deficiency Diseases

  1. Night blindness
  2. Rickets and osteomalacia

Question 29.
Name two water soluble vitamins, their sources and the diseases caused due to their deficiency in diet.
Answer:

Vitamins

  1. Vitamin B<sub>1</sub>
  2. Vitamin C

Sources

  1. Yeast. milk, vegetables.
  2. Citrus fruits, amia and green leafy vegetables.

Deficiency Diseases

  1. Ben – ben
  2. Scurvy (bleeding gums)

Samacheer Kalvi 12th Chemistry Biomolecules 3 mark Question and Answers

VII. Answer the following questions.

Question 1.
Explain the methods of preparation of glucose.
Answer:
1. When sucrose is boiled with diI-H2SO4 in alcoholic solution, hydrolysis take place and glucose and fructose are formed.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-38

2. Glucose is produced commercially by the hydrolysis of starch with dilute HCL at high temperature and pressure.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-39

Question 2.
What happens when glucose reacts with

  1. Br2 / H2O
  2. Conc.HNO3

Answer:
1.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-40

2.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-41

Question 3.
How will you prove the presence of aldehyde group in glucose?
Answer:
Glucose is oxidised to gluconic acid with ammoniacal silver nitrate (Tollen’s reagent) and alkaline copper sulphate (Fehling’s solution). Tollen’s reagent is reduced to metallic silver and Fehling’s solution to cuprous oxide (red precipitate). These reactions confirm the presence of an aldehye group in glucose.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-42
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-43

Question 4.
Define

  1. Epimers
  2. Epimerisation.

Answer:
1. Sugar differing at an asymmetric centre is known as epimers.

2. The process by which one epimer is converted into other is called epimerisation and it requires the enzyme epimersase.

3. Galactose is converted to glucose by this manner in our body.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-44

Question 5.
Explain the methods of preparation of fructose with equations.
Answer:
1. Fructose is obtained from sucrose by heating with dilute H2SO4 (or) with the enzyme invertase.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-45

2. Fructose is prepared commercially by the hydrolysis of Inulin (a polysaccharide) in acidic medium
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-46

Question 6.
What happens when fructose is treated with sodium amalgam and water?
Answer:
When fructose is treated with sodium amalgam and water, partial reduction take place and the products formed are epimers of sorbitol and mannitol. New asymmetric carbon is formed at C – 2. This reaction confirms the presence of keto group in fructose.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-47

Question 7.
Explain about the cyclic structure of fructose?
Answer:
Fructose forms a five membered ring similar to furan. Hence it is called furanose form. When fructose is a component of a saccharide as in sucrose, it usually occurs in furanose form.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-48

Question 8.
Explain about the structure, nature and properties of sucrose.
Answer:
1. Sucrose commonly known as table sugar is the most abundant disaccharide. It is obtained mainly from juice of sugar cane and sugar beets. Insects such as honey bees have the enzyme mvetase that catalyses the hydrolysis of sucrose into glucose and fructose mixture.

2. Honey is primarily a mixture of glucose, fructose and sucrose. On hydrolysis sucrose yields equal amount of glucose and fructose units.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-79

3. Sucrose (+66.6°) and glucose (52.5°) are dextrorotatory compounds while fructose is levo rotatory (- 92.4°)

4. During hydrolysis of sucrose the optical rotation of the reaction mixture changes from dextro to levo. Hence sucrose is also as invert sugar.

5. Structure:
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-49
In sucrose C1 of α – D glucose is joined to C2 of D – Fructose. The glycosidic bond thus formed is called α, 1, 2 – glycosidic bond. Since both the carbonyl carbons are involved in the glycosidic bonding, sucrose is a non – reducing sugar.

Question 9.
Prove that sucrose is

  1. invert sugar
  2. non – reducing sugar.

Answer:
1. Sucrose is an invert sugar: Sucrose (+66.6°) and glucose (+52.5°) are dextro rotatory compounds while fructose is levo rotatory (- 92.4°). During hydrolysis of sucrose, the optical rotation of the reaction mixture changes from dextro to levo. Hence sucrose is also called invert sugar.

2. In sucrose, C1 of α – D glucose is joined to C2 of α – D fructose. The glycosidic bond thus formed is called α – 1, 2 – glycosidic bond. Since both the carbonyl carbons (reducing groups) are involved in the glycosidic bonding, sucrose is a non – reducing sugar.

Question 10.
Write a note about lactose
Answer:
1. Lactose is a disaccharide found in milk of mammals and hence it is referred to as milk sugar.

2. On hydrolysis, it yeilds galactose and glucose. The β – D galactose and β – D glucose are linked by β – 1, 4 – glycosidic bond. the aldehyde carbon is not involved in the glycosidic linkage. Hence it retains its reducing property and is called a reducing sugar.

3. Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-50

Question 11.
Lactose act as reducing sugar. Justify this statement.
Answer:

  1. Lactose is a disaccharide and contains one galactose unit and one glucose unit.
  2. In lactose, the β – D galactose and β – D glucose are linked by β – 1, 4 – glycosidic bond.
  3. The aldehyde carbon is not involved in the glycosidic bond hence it retains its reducing property and is called a reducing sugar.

Question 12.
Write about maltose with its structure.
Answer:
1. Maltose is extracted from malt and it is called malt sugar. Malt from sprouting barely is the major source of maltose. Maltose is produced during digestion of starch by the enzyme α – analyse.

2. Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-51

3. Maltose consists of two molecules of α – D glucose units linked by an α – 1, 4 – glycocidic bond between anomeric carbon ofone unit and C – 4 of the other unit. Since one of the glucose has the carbonyl group intact it act as a reducing sugar.

Question 13.
Sucrose and maltose are disaccharides but sucrose Is a non reducing sugar while maltose Is a reducing sugar. Give reason.
Answer:
1. Sucrose is a disaccharide that composed of α – D glucose and β – D fructose. In sucrose Cl of α – D glucose is joined to C2 of D – fructose. The glycosidic bond thus formed is called α – 1, 2- glycosidic bond. Since both the carbonyl carbons (reducing carbons) are involved in the glycosidic bonding, sucrose is a non-reducing sugar.

2. But maltose contains two molecules of x – D glucose units that are linked by an α – 1, 4 – glycosidic bond. Anomeric carbon of one unit and C – 4 of other unit are connected together. Smce one of the glucose bas the carbonyl group intact it acts as reducing sugar.

Question 14.
Give brief account of nature and structure of cellulose.
Answer:
1. Cellulose is the major constituent of plant cell walls. Cotton is almost pure cellulose. On hydrolysis, cellulose yields D – glucose molecules

2. Cellulose is a straight chain polysaccharide. The glucose molecules are linked by β (1, 4 -) glycoside bond.

3. Structure of cellulose.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-52

Question 15.
What are the uses of cellulose?
Answer:

  1. Cellulose is used extensively in manufacturing paper, cellulose fibres and rayon explosive.
  2. Gun cotton – nitrated ester of cellulose an explosive is prepared from cellulose.
  3. Cellulose act as food for animals

Question 16.
Human cannot use cellulose as food – Why?
Answer:
Human cannot use cellulose as food because our digestive systems do not contain the necessary enzymes such as glycosidases (or) cellulases that can hydrolyse the cellulose. But animals contain cellulose enzyme in their digestive system and they can digest cellulose. So cellulose can used as food for animals but not for human.

Question 17.
What are the major classification of proteins? Give example?
Answer:
1. Proteins are classified based on their structure into two major types. They are fibrous protein and glubular protein.

2. Fibrous proteins are linear molecules similar to fibres. They are generally insoluble in water and are held together by disulphide bridges and weak inter molecular hydrogen bonds. These proteins often used as structural proteins. Example, Keratin, Collagen.

3. Globular proteins have an overall spherical shape. The poly peptide chain is folded into a spherical shape. These proteins are usually soluble in water and have many functions including catalysis.

Question 18.
Explain the mechanism of enzyme action?
Answer:
1. Enzymes are bio catalysts that catalyse a specific bio chemical reaction. They generally activate the reaction by reducing the activation energy by stabilising the transition state.

2. In a typical reaction, enzyme E binds with the substrate molecule leversity to produce an enzyme – sybstate complex. During this stage the substrate is converted into product and

3. Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-53

Question 19.
Explain about the nature, classification and properties of lipids (or) write a note about lipids.
Answer:
1. Lipids are organic molecules that are soluble in organic solvents such as chloroform and methanol and are insoluble in water. Lipids means fat. They are the principal component of cell membrane including cell walls.

2. Lipids act as energy source for living systems. Fat provide 2 – 3 fold higher energy compared to carbohydrates or proteins.

3. Based on their structure, lipids can be classified as simple lipids, compound lipids and derived lipids.

4. simple lipids can be further classified into fats, which are esters of long chain fatty acids fats, with glycerol (triglycerides) and waxes which are esters of fatty acid with long chain monohydric alcohols (Bees wax)

5. Compound lipids are the esters of simple fatty acid with glycerol which contain additional group. Based on the groups attached, they are further classified into phospholipids, glycolipids and lipproteins. Phospho lipids contain a phospho ester linkage while the glycolipids contain a sugar molecule attached. The iipo proteins are complexes of lipid with proteins.

Question 20.
Write the chemical name, sources and deficient disease of the following.

  1. Vitamin D
  2. Vitamin E
  3. Vitamin K

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-54

Question 21.
What are the biological functions of nucleic acids?
Answer:

  1. Energy carriers (ATP)
  2.  Components of enzyme cofactors. Example – Co enzyme A, NAD, FAD
  3. Chemical messengers. Example – Cyclic AMP, CAMP

Question 22.
What happens when D – glucose is treated with the following reagents?

  1. HI
  2. Bromine water
  3. HNO3

Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-55

2.Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-56

3. Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-57

Question 23.
Define the following as related to proteins.

  1. Peptide linkage
  2. Primary structure
  3. Denaturation

Answer:
1. Peptide linkage:
Amino acids are bifunctional molecules with NH2 group at its one end and COOH at the other. Therefore, the COOH of one molecule and NH2 of another molecule can interact with elimination of a H,O molecule to form an amide like linkage called peptide bond or peptide linkage.

2. Primary structure:
The sequence in which amino acids are linked together in a polypeptide chain forms the primary structure.

3. Denaturation:
The process by which secondary and tertiary structure of proteins get disturbed by change of pH or temperature, so that they are not able to perform their functions, is called denaturation of proteins.

Question 24.
Difference between Globular and fibrous proteins.
Answer:
Globular proteins

  1. They form α – helix structure
  2. They are soluble in water.
  3. They are cross lined condensation polymers of acidic and basic amino acids.

Fibrous Proteins

  1. They have – plcated structure.
  2. They are insoluble in water.
  3. They are linear condensation polymeric proteins.

Question 25.
Explain what is meant by

  1. a peptide linkage
  2. a glycosidic linkage.

Answer:
1. Peptide linkage:
Polymers of x – amino acids are connected to each other by peptide bond or peptide linkage. Chemically peptide linkage is an amide formed between – COOH group and NH2 group.

2. Glycosidic linkage:
The two monosaccharide units are joined together by an oxide linkage formed by the loss of a water molecule. Such a linkage between two mono saecharide units through oxygen atom is called glycosidic linkage.

Question 26.
What are essential and non-essential amino acids? Give one example of each type.
Answer:
1. Essential amino acids:
Amino acids which are not synthesised by the human body are called essential amino acids. Example – Valine, Leucinc.

2. Non – essential amino acids:
Amino acids which are synthesised by human body are called non – essential amino acids. Example – Glycine, Aspartic acid, etc.

Question 27.
Mention the type of linkage responsible for the formation of the following.

  1. Primary structure of proteins
  2. Cross linking of polypeptide chains.
  3. α – helix formation
  4. β – sheet structure.

Answer:
Type of Structure

  1. Primary structure of proteins
  2. Cross linking of polypeptide chains
  3. α – helix
  4. β – sheet structure

Type of linkages

  1. Peptide bond or peptide linkage
  2. Polypeptide linkage
  3. Hydrogen bond
  4. Intermolecular hydrogen bond

Question 28.
Name the chemical components which constitute nucleotides. Write any two functions of nucleotides in a cell.
Answer:
Nucleotides are made up of a heterocyclic base containing nitrogen, a five carbon atom – moeity and a phosphate group.
Example:

  1. AMP (adenosine monophosphate)
  2. ADP (adenosine diphosphate) and
  3. ATP (adenosine triphospate)

Functions:

  1. Act as energy carriers
  2. They synthesise proteins

Question 28.
Name the main disease caused due to lack of vita min and its source in each of the following. A, B6 and E.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-58

Question 29.
Define the following and give one example of each.

  1. Isoelectric point
  2. Mutarotation
  3. Enzymes

Answer:
1. Isoelectric point:
It is the pH at which +ve and – ve charges on zwitter ion are equal. Example amino acid exists as zwitter ion at pH = 5.5 to 6.3.

2. Mutarotation:
It is a spontaneous change in optical rotation when an optically active substance is dissolved in water. Example α – glucose, when dissolved in water, then its optical rotation changes from 1110 to 52.5°.

3. Enzymes:
Enzymes are biocatalysts which speeds up the reactions in biosystems. They are highly specific and selective in their action. Chemically all enzymes are proteins.

Question 30.
What is denaturation and renaturation of proteins? Give reason: Amylose present in the saliva becomes inactive in the stomach.
Answer:
1. The process of disruption of 2° and 3° structure of proteins without changing its primary structure is called denaturation.

2. In stomach the pH is acidic, therefore amylose becomes inactive. That is why digestion of carbohydrates does not take place in stomach.

Question 31.
Define the following terms.

  1. Nucleotide
  2. Anomers
  3. Essential amino acids

Answer:
1. Nucleotide:
It is the monomer unit of DNA which is formed by a nitrogenous base, deoxyribose sugar and phosphoric acid.

2. Anomers:
Anomers are cyclic monosaccharides which are differing from each other in the configuration of C – 1 if it is an aldose or in the configuration at C – 2 if it is a ketose.

3. Essential amino acids:
The amino acids cannot be synthesised by the body and are essential for the body.

Question 32.
Which one of the following is disaccharide.

  1. Starch, Maltose, Fructose, Glucose.
  2. Write the name of vitamin whose deficiency causes bone deformities in children.

Answer:

  1. Maltose
  2. Vitamin D

Quesiton 33.
Write the major classes in which the carbohydrates are divided depending upon whether thee undergo hydrolysis and if so, the number of products formed.
Answer:
On the basis of hydrolysis, carbohydrates are divided into three major classes:
1. Monosaccharides. These cannot be hydrolysed into simpler molecules. These are further classified as aldoses, and ketoses.

2. Oligosaccharides. These carbohydrates on hydrolysis give 2-10 units of mono-saccharides. For example – Sucrose.

3. Polysaccharides. These are high molecular mass carbohydrates which give many molecules of monosaccharides on hydrolysis. Form example: Cellulose, starch.

Question 34.

  1. What changes occur in the nature of egg proteins on boiling?
  2. Name the type of bonding which stabilises the a-helix structure in proteins.

Answer:
1. On boiling, protein of egg gets denatured. Thus, due to coagulation water get absorbed.

2. Hydrogen bonding between
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-59

Question 35.
Answer the following questions briefly.

  1. What are reducing sugars?
  2. What is meant by denatu ration of a protein?
  3. How is oxygen replenished in our atmosphere?

Answer:
1. Reducing sugar:
All those carbohydrates which reduce Fehling’s solution and Tollens’ reagent are referred to as reducing sugars. All monosaccharides whether aldose or ketose are reducing sugars.

2. Denaturation of a protein:
When 2° and 3° structure of a protein is destroyed due to the physical changes like temperature, change in pH, it is called denaturation of a protein.
Example: Coagulation of egg white on boiling.

3. We take oxygen from atmosphere and release CO2. Plants take up CO2 and H2O from the atmosphere to prepare their food in the presence of sunlight and release O2 thus O2 is replenished in atmosphere.

Samacheer Kalvi 12th Chemistry Biomolecules 5 mark Questions Answers

VIII.Answer the following questions.

Question 1.
How would you prove the structure of glucose? (OR) Elucidate the structure of glucose.
Answer:
1. Elemental analysis and molecular weight determination show that the molecular formula of glucose is C6H12O6.

2. On reduction with Conc.HI and red P at 373K, glucose gives a mixture of n – hexane and 2 – iodohexane indicating that the six carbon atoms are bonded linearly.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-60

3. Glucose reacts with hydroxylamine to form oxime and with HCN to form cyanohydrin. These reactions indicate the presence of carbonyl group in glucose.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-61

4. Glucose gets oxidised to gluconic acid with bromine water with bromine water suggests that the carbonyl group is an aldchyde group and it occupies one end of the carbon chain. When glucose is oxidised by conc.HNO3, glucaric acid is formed and it suggest that the other end Id occupied by a primary alcoholi.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-62

5. Glucose is oxidised to gluconic acid with ammoniacal silver nitrate (Toiles reagent) and alkaline copper sulphate (Fehling’s solution). These reactions further confirm the presence of an aldehyde group.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-63

6. Glucose forms penta acetate with acetic anhydride suggesting the presence of five alcohol groups.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-64

7. Glucose is a stable compound and does not undergo dehydration easily. It indicates that not more than one hydroxyl group is bonded to a single carbon atom. Thus the five hydroxyl groups are attached to five different carbon atoms and the sixth carbon is an aldehyde group.

8. The exact special arrangement of – OH groups was given by Emil Fischer as follows.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-65

9. D (+) glucose has D configuration and it is dextro rotatoly.

Question 2.
Explain about the cyclic structure of Glucose.
Answer:
1. Fischer identified that the open chain Penta hydroxyl aldehyde structure of glucose that he proposed did not completely explain its chemical behaviour.

2. Unlike simple aldehyde, glucose did not form crystalline hisuiphite compound with sodium bisuiphite. Glucose does not give Schifis test and pent.a acetate derivative of glucose was not oxidised by Tollen’s reagent. This behaviour could not be explained by open chain structure.

3.Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-66

4. In order to explain these it was proposed that one of the hydroxyl group reacts with aldehyde group to form a cyclic structure (hemiacetal form). This also results in the conversation of the achiral aldehyde carbon into a chiral one leading the possibility of two isomers. These two isomers differ only in the configuration of C1 carbon. These isomers are called anomers.

5. The two anomeric forms of glucose are called – and β – forms. This cyclic structure of glucose is similar to pyran, a cyclic compound with 5 carbon and one oxygen atom, and hence is called pyranose form.

6. The specific rotation of pure α – and 3 – (D) glucose are 112° & 18.7° respectively. However, when pure form any one of these sugars dissolved in water, slow interconversion of – D glucose and β – D glucose via open chain form until equilibrium is established giving constant specific rotation + 53°. This phenomenon is called mutarotation.

Question 3.
Explain about the structure of Fructose. (OR) Elucidate the structure of Fructose.
Answer:
1. Elemental analysis and molecular weight determination of fructose show that it has the molecular formula C6H12O6.

2. Fructose on reduction with Hl and red phosphoms gives a mixture of n – hexane (major product) and 2 – iodohexane (minor product). This reaction indicates that the six carbon atoms in fructose are in a straight chain.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-67

3. Fructose reacts with NH2OH and HCN. It shows the presence of carbonyl groups in the molecules of fructose.

4. Fructose reacts with acetic anhydride in the presence of pyridine to form penta acetate. This reaction indicates the presence of’ five hydroxyl groups in a fructose molecule.

5. Fructose is not oxidized by bromine water. This rules out the possibility of presence of an aldehyde (-CHO) group.

6. Partial reduction of fructose with sodium amalgam and water produces mixtures of sorbitol and mannitol which are epimers at second carbon. New asymmetric carbon is formed at C – 2. This confirms the presence of keto group.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-68

7. On oxidation with nitric acid, it gives glycolic acid and tartane acids which contain smaller number of carbon atoms than in fructose. This shows that a keto group is present in C – 2. It also shows the presence of 10 alcoholic groups at C- 1 and C- 6. From the above reaction the structure of fructose is
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-69

This shows that a keto group is present in C – 2. It also shows the lpresence of 10 alcoholic groups at C – 1 and C – 6. From the above reaction the structure of fructose is
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-70

Question 4.
Describe about the structure, nature and properties of starch.
Answer:

  1. Starch is used for energy storage in plants. Potatoes, corn, wheat and rice are the rich sources of starch.
  2. It is a polymer of glucose in which glucose molecules are lined by α (1,4) glycosidic bonds.
  3. Starch can be separated into two fractions namely, water soluble amylose and water insoluble amylo pectin. Starch contain about 20% of amylase and about 80% amylopectin.
  4. Amylose is composed of unbranched chains upto 4000 α – D glucose molecules joined by α (1,4) glycosidic bonds.
  5. At branch points, new chains of 24 to 30 glucose molecules are linked by α (1,6) glycosidic bonds with iodine solution amylose gives blue colour while amylo pectin gives a purple colour.

Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-72

Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-73

Question 5.
Explain about the structure of proteins.
Answer:
1. Proteins are polymers of amino acids. Their three dimensional structure depends mainly on the sequence of amino acids. The protein structure can be described at four hierarchal levels called primary, secondary, tertiary and quaternary structures.

Primary structure of proteins:
Proteins are polypeptide chains made up of amino acids connected through peptide bonds. The relative arrangement of the amino acids in the polypeptide chain is called the primary structure of the protein.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-74

Secondary structure of proteins:
The amino acids in the polypeptide chain forms highly, regular shapes through the hydrogen bond between the carbonyl oxygen and the
neighbouring amine hydrogen of the main chain, α – Helix and β – strands or sheets are two most common substructures formed by proteins.

α – Helix:
In the α – helix sub – structure, the amino acids are arranged in a righthanded helical (spiral) structure and are stabilised by the hydrogen bond. The side chains of the residues protrude outside of the helix. Each turn of an α – helix contains about 3.6 residues and is about 5.4 A long.

β – Strands:
β – Strands are extended peptide chain rather than coiled. The hydrogen bond occur between main chain carbonyl group one such strand and the amino group of the adjacent strand resulting in the formation of a sheet like structure. This arrangement is called β – sheets.

Tertiary structure:
The secondary structure elements (α – helix & β – sheets) further folds to form a three dimensional arrangement. This tertiary structure of proteins are stabilised by the interactions between the side chains of the amino acids. These interactions include the disulphide bridges between cysteine residues, electrostatic, hydrophobic, hydrogen bonds and van der Waals interactions.

Quaternary Structure:
The oxygen transporting protein, haemoglobin contains four polypeptide chains while DNA polymerase enzyme that make copies of DNA, has ten polypeptide chains. In these proteins the individual polypeptide chains interacts with each other to form the multimeric structure which known as quaternary structure. The interactions that stabilises the tertiary structures also stabilises the quaternary structures.

Question 6.
What are the biological importance of proteins?
Answer:
Proteins are the functional units of living things play vital role in all biological processes

  1. All biochemical reactions occur in the living systems are catalysed by the catalytic proteins called enzymes.
  2. Proteins such as keratin, collagen acts as structural back bones.
  3. Proteins are used for transporting molecules (Haemogiobin), organelles (Kinesins) in the cell and control the movement of molecules in and out of the cells (Transporters).
  4. Antibodies help the body to fight various diseases.
  5. Proteins are used as messengers to coordinate many functions. Insulin & glucagon controls the glucose level in the blood.
  6. Proteins act as receptors that detect presence of certain signal molecules and activate the proper response.
  7. Proteins are also used to store metals such as iron (Femtin) etc.

Question 7.
Write the chemical name, source and deficient disease of the following

  1. Vitamin A
  2. Vitamin B1
  3. Vitamin B2
  4. Vitamin B3
  5. Vitamin B5

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-75

Question 8.
Write the chemical name, source and deficient disease of the following

  1. Vitamin B6
  2. Vitamin B7
  3. Vitamin B9
  4. Vitamin B12
  5. Vitamin C

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-76

Question 9.
Explain about the composition and structure of nucleic acids.
Answer:
1. Nucleic acids are biopolymers of nucleotides. Controlled hydrolysis of DNA and RNA yields three components namely a nitrogeneous base, a pentose sugar and phosphate group.

2. Nitrogen base.
(a) These are nitrogen containing organic compounds which are derivatives of two parent compounds, pyrimidine and purine.
(b) Both DNA and RNA have two major purine bases, adenine (A) and guanine (G). In both DNA and RNA, one of the pyrimidines is cytosinc (C), but the second pyrimidine is thymine (T) ¡n DNA and uracil (U) in RNA.

3. Pentose Sugar.
Nucleic acids have two types ofpentoses. The recurring deoxyribonucleotide units of DNA contain 2’ – dcoxy – D – ribose and the ribonucleotide units of RNA contain D – ribose. In nucleotides, both types of pentoses are in their – furanose form.

4. Phosphate group.
Phosphoric acid forms phosphor diester bond between nucleotides. Based on the number of phosphate group present in the nucleotides, they are classified mono nucleotide, dinucleotide and trinucleotide.

5. The molecule without the phosphate group is called a nucleoside. A nucleotide is derived from a nucleoside by the addition of a molecule of phosphoric acid.

6. Sugar + Base → Nucleoside
Nucleoside + Phosphate → Nucleotidc
Nucleotide → Polynucleotide (Nucleic Acid)

Question 10.
Describe about the double strand helix structure of DNA.
Answer:
1. Watson and Crick postulated a 3 – dimensional model of RNA structure which consisted of two antiparallel helical DNA chains wound around the same axis to form a right handed double helix.

2. Th e hydrophilic backbones of alternating deoxyribose and phosphate groups are on the outside of the double helix, facing the surrounding water. Th e purine and pyrimidine bases of both strands are stacked inside the double helix,

with their hydrophobic and ring structures very close together and perpendicular to the long axis, thereby reducing the repulsions between the charged phosphate groups. The offset pairing of the two strands creates a major groove and minor groove on the surface of the duplex.

3. The model revealed that there are 10.5 pairs (36A°) per turn of the helix and 3.4A° between the stacked bases. They also found that each base is hydrogen bonded to a base in opposite strand to form a planar base pair.

4. Two hydrogen bonds are formed between adenine and thymine and three hydrogen bonds are formed between guanine and cytosine. Other pairing tends to destablize the double helical structure. This specific association of the two chains of the double helix is known as complementary base pairing.

5. The DNA double or duplex is held together by two forces.

  • Hydrogen bonding between complementary base pairs.
  • Base – stacking interactions.

The complementary between the DNA strands is attributable to the hydrogen bonding between base pairs but the base stacking interactions are largely non-specific, make the major contribution to the stability of the double helix.
Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-77

Question 11.
Explain about the types of RNA molecules.
Answer:
1. Ribonucleic acids are similar to DNA. Cells contain upto eight times high quantity of RNA than DNA. RNA is found in large amount in the cytoplasm and a lesser amount in the nucleus.

2. RNA molecules are classified according to their structure and function into three major types.

  1. Ribosomal RNA (r – RNA)
  2. Messenger RNA (m – RNA)
  3. Transfer RNA (t – RNA)

3. r – RNA:
r – RNA is mainly found in cytoplasm and in ribosomes, which contain 60% RNA and 40% protein. Ribosomes are the sites at which protein synthesis takes place.

4. t – RNA:
t – RNA molecules have lowest molecular weight of all nucleic acids. They consist of 73 – 94 nucleotides in a single chain. The function of t – RNA is to carry amino acids to the sites of protein synthesis on ribosomes.

5. m – RNA:
m – RNA is present in small quantity and very short lived. They are single stranded and their synthesis take place on DNA. The synthesis m-RNA from DNA strand is called transcription. m – RNA carries genetic information from DNA to the ribosomes for protein synthesis.

Question 12.
Explain about DNA finger printing process.
Answer:
1. DNA finger printing is one of the most accurate methods for placing an individual at the scene of a crime has been a finger print.

2. The DNA finger print is unique for every person and can be extracted from traces of sample from blood, saliva, hair etc. By using this method, we can detect the individual specific variation in human DNA.

3. In this method, the extracted DNA is cut at specific points of varying lengths in the formation of DNA fragments of varying lengths which were analysed by technique called gel electrophoresis. This method separates the fragments based on their size. The gel containing the DNA fragments are then transferred to a nylon sheet using a technique called blotting. Then the fragments will undergo autoradiography in which they were exposed to DNA probes.

4. A piece of X-ray film was then exposed to the fragments, and a dark mark was produced at any point where a radioactive probe had become attached. The resultant pattern of marks could then be compared with other samples.

5. DNA finger printing is based on slight sequence differences between individuals. These methods are providing decisive in court cases world wide.

Common Errors

  1. Carbohydrates & Enzyme names are different.
  2. Peptide bond and amide bond are different.
  3. Vitamins: Solubility based classification
  4. Main source of vitamin

Rectifications

1. Carbohydrates name should end as – ose.
Eg. Diatose, maltose
Enzyme name should end as – ase.
Eg. Diastase, maltase

2. Samacheer Kalvi 12th Chemistry Solutions Chapter 14 Biomolecules-78

3. Vitamin A, D, E, K – fat soluble. Vitamin C, B complex are water soluble.

4. Milk:
Vitamin A, B1, B2, B6, B7, D (6 Vitamins)
Green Vegetables:
B1, B3, B7, K (4 vitamins)
Liver:
B1, B2, B3, B7

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Samacheer Kalvi 12th Chemistry Chapter 10 Surface Chemistry Textual Evaluation Solved

Samacheer Kalvi 12th Chemistry Surface Chemistry Multiple Choice Questions

Question 1.
For freudlich isotherm a graph of log \(\frac{x}{m}\) is plotted against log P. The slope of the line and its y – axis intercept respectively corresponds to
(a) \(1 / n\), k
(b) log \(1 / n\), k
(c) \(1 / n\), log k
(d) log \(1 / n\), log k
Answer:
(c) \(1 / n\), log k
\(\frac{x}{m}\) = \(\mathrm{k} \cdot \mathrm{p}^{1 / \mathrm{n}}\)
log\((\frac{x}{m})\) = log k + \(\frac { 1 }{ n }\)log p
y = c + mx
m = \(\frac { 1 }{ n }\) and c = log k

Question 2.
Which of the following is incorrect for physisorption?
(a) reversible
(b) increases with increase in temperature
(c) low heat of adsorption
(d) increases with increase in surface area
Answer:
(b) increases with increase in temperature
Physisorption is an exothermic process. Hence increase in temperature decreases the physisorption.

Question 3.
Which one of the following characteristics are associated with adsorption?
(a) ∆G and ∆H are negative but ∆S is positive
(b) ∆G and ∆S are negative but ∆H is positive
(c) ∆G is negative but ∆H and ∆S are positive
(d) ∆G. AH and ∆S all are negative.
Answer:
(d) ∆G, ∆H and ∆S all are negative.
Adsorption leads to decrease in randomness (entropy).i.e. ∆S < 0 for the adsorption to occur, ∆G should be – ve. We know that ∆G = ∆H – T∆S if ∆S is – ve, T∆S is + ve. It means that ∆G will become negative only when ∆H is – ve and ∆H > T∆S

Question 4.
Fog is colloidal solution of ……………..
(a) solid in gas
(b) gas in gas
(c) liquid in gas
(d) gas in liquid
Answer:
(c) liquid in gas
dispersion medium-gas, dispersed phase-liquid

Question 5.
Assertion: Coagulation power of Al3+ is more than Na.
Reason: greater the valency of the flocculating ion added, greater is its power to cause precipitation
(a) if both assertion and reason are true and reason is the correct explanation of assertion.
(b) if both assertion and reason are true but reason is not the correct explanation of assertion.
(c) assertion is true but reason is false
(d) both assertion and reason are false
Answer:
(a) if both assertion and reason are true and reason is the correct explanation of assertion. (Hardy-Sechuize nile)

Question 6.
Statement: To stop bleeding from an injury, ferric chloride can be applied. Which comment about the statement is justified?
(a) It is not true, ferric chloride is a poison.
(b) It is true, Fe3+ ions coagulate blood which is a negatively charged sol
(c) It is not true; ferric chloride is ionic and gets into the blood stream.
(d) It is true, coagulation takes place because of formation of negatively charged sol with Cl.
Answer:
(b) It is true, Fe3+ ions coagulate blood which is a negatively charged sol

Question 7.
Hair cream is …………..
(a) gel
(b) emulsion
(c) solid sol
(d) sol.
Answer:
(b) emulsion
Emulsion dispersed phase, Dispersion medium -liquid

Question 8.
Which one of the following is correctly matched?
(a) Emulsion – Smoke
(b) Gel – butter
(c) foam – Mist
(d) whipped cream – sol
Answer:
(b) Gel – butter

Question 9.
The most effective electrolyte for the coagulation of As2S3 Soils
(a) NaCI
(b) Ba(NO3)2
(c) K3[Fe(CN)6]
(d) AI3+
Answer:
(d) AI3+
As2S3 is a – vely charged colloid. It will be most effectively coagulated by the cation with greater valency. i.e., Al3+.

Question 10.
Which one of the is  not a surfactant?
(a) CH3 – (CH2)15 – N – (CH3)2CH2Br
(b) CH3 – (CH2)15 – NH2
(c) CH3 – (CH2)16 – CH2OSO2 – Na+
(d) OHC – (CH2)14 – CH2 – COONa+
Answer:
(b) CH3 – (CH2)15 – NH2

Question 11.
The phenomenon observed when a beam of light is passed through a colloidal solution is ………….
(a) Cataphoresis
(b) Electrophoresis
(c) Coagulation
(d) Tyndall effect
Answer:
(d) Tyndall effect-scattering of light

Question 12.
In an electrical field, the particles of a colloidal system move towards cathode. The coagulation of the same sol is studied using K2SO4
(i). Na3PO4
(ii). K4[Fe(CN)6]
(iii). and NaCI
(iv). Their coagulating power should be …………..
(a) II > I >IV > III
(b) III > II > I > IV
(c) I > II > III > IV
(d) none of these
Answer:
(b) III > II > I > IV

Question 13.
Collodion is a 4% solution of which one of the following compounds in alcohol – ether mixture?
(a) Nitroglycerine
(b) Cellulose acetate
(c) Glycoldinitrate
(d) Nitrocellulose
Answer:
(a) Nitrocellulose
pyroxylin (nitro cellulose)

Question 14.
Which one of the following is an example for homogeneous catalysis?
(a) manufacture of ammonia by Haber’s process
(b) manufacture of sulphuric acid by contact process
(c) hydrogenation of oil
(a) Hydrolysis of sucrose in presence of all HCI
Answer:
(a) Hydrolysis of sucrose in presence of all HCl
Both reactant and catalyst are in same phase. i.e. (1)

Question 15.
Match the following.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-1
Answer:
(a) (iv) (i) (ii) (iii)

Question 16.
The coagulation values in millimoles per litre of the electrolytes used for the coagulation of AS2S3 are given below
(I) (NaCI) = 52
(II) (BaCl) = 0.69
(III) (MgSO4) = 0.22
The correct order of their coagulating power is ……….
(a) III > II > I
(b) I > II > III
(c) I >III > II
(d) II > III > I
Answer:
(a) III > II > I
coagulating power ± \(\frac{1}{\text { coagulation value }}\)

Question 17.
Adsorption of a gas on solid metal surface is spontaneous and exothermic, then ……………
(a) ∆H increases
(b) ∆S increases
(c) ∆G increases
(d) ∆S decreases
Answer:
(a) ∆S decreases – ∆S is -ve

Question 18.
If x is the amount of adsorbate and m is the amount of adsorbent, which of the following relations is not related to adsorption process?
(a) x/m = f(P) at constant T
(b) x/m = f(T) at constant P
(c) P = f(T) at constant x/m
(d) x/m = PT
Answer:
(d) x/m = mPT

Question 19.
On which of the following properties does the coagulating power of an ion depend?
(a) Both magnitude and sign of the charge on the ion.
(b) Size of the ion alone
(c) the magnitude of the charge on the ion alone
(d) the sign of charge on the ion alone.
Answer:
(a) Both magnitude and sign of the charge on the ion.

Question 20.
Match the following.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-2
Answer:
(d) (iv) (iii) (ii) (i)

Samacheer Kalvi 12th Chemistry Surface Chemistry Short Answer Questions

Question 1.
Give two important characteristics of physisorption.
Answer:
Important characteristics of physisorption:

  1. It is reversible
  2. It has low heat of adsorption
  3. It has weak van der Waals forces of attraction with adsorbent.
  4. It increases with increase in pressure.
  5. It forms multimolecular layer.

Question 2.
Differentiate physisorption and chemisorption.
Answer:
Chemical adsorption orChemisorption or Activated adsorption

  1. It is very slow
  2. It is very specific depends on nature of adsorbent and adsorbate.
  3. chemical adsorption is fast with increase pressure, it can not alter the amount.
  4. When temperature is raised chemisorption first increases and then decreases.
  5. Chemisorption involves transfer of electrons between the adsorbent and adsorbate,
    Heat of adsorption is high i.e., from 40 – 400kJ/mole.
  6. Monolayer of the adsorbate is formed.
  7. Adsorption occurs at fixed sites called active centres. It depends on surface area .
  8. Chemisorption involves the formation of activated complex with appreciable activation energy.
  9. Physical adsorption or van der waals adsorption or Physisorptlon
  10. It is irreversible

Physical adsorption or van der waals adsorption or physisorption.

  1. It is instantaneous
  2. It is non-specific
  3. In Physisorption. when pressure increases the amount of adsorption increases.
  4. Physisorption decreases with increase in temperature.
  5. No transfer of electrons
  6. Heat of adsorption is low in the order of 4OkJ/mole.
  7. Multilayer of the adsorbate is formed on the adsorbent.
  8. It occurs on all sides.
  9. Activation energy is insignificant.
  10. It is reversible.

Question 3.
In case of chemisorption, why adsorption first increases and then decreases with temperature?
Answer:
1. Chemisorption involves a high activation energy so it is also referred to as activated adsorption.

2. It is found in chemisorption that it first increases and then decreases with increase in temperature. When adsorption is plotted, the graph first increaes and then decreases with temperature.

3. The initial increase illustrates the requirement of activation of the surface for adsorption is due to fact that formation of activated complex requires certain energy. But later it decreacs at high temperature is due to desorption as the kinetic energy of the adsorbate increases (exothermic nature)

Question 4.
Which will be adsorbed more readily on the surface of charcoal and why; NH3 or CO2?
Answer:
1. The gaseshaving low critical temperature are adsorbed slowly, while gases with high critical temperature are adborbed readily.

2. Among CO2, and NH3, NH3 will be more readily adsorbed on the surface of the charcoal. This is because the critical temperature of ammonia gas is quite high than the CO2. Hence, it easily combines with the materials than the CO2 whether it is solid, liquid or any gases.

Question 5.
Heat of adsorption is greater for chemisorptions than physisorption. Why?
Answer:
Chemisorption has higher heat of adsorption. because in chemisorption the chemical bonds are much stronger. In adsorbed state the adsorbate is hold on the surface of adsorbent by attractive forces (bond). And chemisorption is irreversible one. Therefore, heat of adsorption is greater for chenil sorptions than physisorption. Chemisorption, heat of adsorption range 40 – 400kJ/mole.

Question 6.
In a coagulation experiment 10 mL of a colloid (X) is mixed with distilled water and 0.1M solution of an electrolyte AB so that the volume is 20 mL. It was found that all solutions containing more than 6.6 mL of AB coagulate with in 5 minutes. What is the flocculation values of AB for sol (X)?
Answer:
A minimum of 6.6mL of AB is required to coagulate the sol. The moles of AB in the sol is
\(\frac{6.6 \times 0.01}{20}\) = 0.033 moles
This means that a minimum of 0.033 moles or 0.0033 x 1000 = 3.3 milli moles are required for coagulating one litre of sol. Flocculation value of AB for X = 3.3

Question 7.
Peptising agent is added to convert precipitate into colloidal solution. Explain with an example.
Answer:
1. Ions either positive or negative of peptizing agent (electrolyte) are adsorbed on the particles of precipitate. They repel and hit each other and break the particles of the precipitate into colloidal size.

2. For example, when we add a small volume of very dilute hydrochloric acid solution peptising agent to a fresh precipitate of a silver chloride, it leads to formation of silver chloride colloidal solution,
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-3

Question 8.
What happens when a colloidal sol of Fe(OH)3 and As2S3 are mixed?
Answer:
On mixing Fe(OH)3 positive sol and As2S3 negative sol, mutual coagulation occurs which causes precipitation. When these sol got mixed with each other, due to Fe3+ and S2- ions neutralisation of charges will happen and precipitate will be formed.
Fe(OH)3 + As2S3 → Fe2S3 + As(OH)3

Question 9.
What is the difference between a sol and a gel?
Answer:
Sol

  1. The liquid state of a colloidal solution is called sol.
  2. The sol does not have a definite structure.
  3. The dispersion medium of the sol may be water.
  4. The sol can be converted to gel by cooling The sol can be easily dehydrated.
  5. The viscosity of the sol is very low.
  6. Sol is categorized into lyophobic and lyophilic sols.
  7. Example: Blood

Gel

  1. The solid or semi solid state of a colloidal solution is called gel.
  2. The gel possesses honey comb like structure.
  3. The dispersion medium of gel will be hydrated colloid particles.
  4. The gel can be converted sol by heating.
  5. The gel cannot be dehydrated.
  6. The viscosity of the gel is very high.
  7. There is no such classification of gel.
  8. Example: Fruit jelly, cooked gelatin jelly.

Question 10.
Why are lyophillic colloidal sols are more stable than lyophoblic colloidal sol?
Answer:
1. A lyophilic colloidal sols are stable due to the charge and the hydration of sol particles.

2. Lyophilic sols are more stable than lyophobilc sols because they are highly hydrated in the solution. And since more is the hydration more will be its stability.

3. Lyophilic sols are stabilized by electrostatic charge and hydration where as lyophobile sols are only stabilized by charge, so they easily gets coagulated and requires a stabilising agent. Hence, lyophilic sols are more stable than the lyophobilc sols.

Question 11.
Addition of Alum purifies water. Why?
Answer:
Purification of drinking water is activated by coagulation of suspended impurities in water using alums containing Al<sup>3+</sup>. That is why we are adding to purify water.

Question 12.
What are the factors which influence the adsorption of a gas on a solid?
Answer:
Factors which influence the adsorption of a gas on a solid is as follows:
1. Nature of the gas:
Easily liquifiable gases such as NH3, HCl etc are adsorbed to a great extent in comparison to gases such as H2, O2 etc. This is because van der Waal’s forces are stronger is easily liquifiable gases.

2. Surface area of the solid:
The greater the surface area of the adsorbant, the greater is the adsorption of gas on the solid surface.

3. Effect of pressure:
Adsorption is a reversible process and is accompanied by a decrease in pressure. Therefore, adsorption increases with an increase in pressure.

4. Effect of temperature:
Adsorption is an exothermic process. Thus in accordance with Le – Chatelier’s principle, the magnitude of adsorption decreases with an increase in temperature.

Question 13.
What are enzymes? Write a brief note on the mechanism of enzyme catalysis.
Answer:
Enzymes are complex protein molecules with three dimensional structures. They catalyse the chemical reaction in living organism. They are often present in colloidal state and extremely specific in catalytic action.

Each enzyme produced in a particular living cell can catalyse a particular reaction in the cell. Mechanism of enzyme catalysis: Mechanism of enzyme catalysed reaction is known as lock and key mechanism.
1. Enzymes arc highly specific in their action.

2. These specificity is due to the pressure of active sites. The shape of active site of any given enzyme is like cavity such that only a specific substrate can fit into it.

In the same way a key fit into lock. The specific binding needs to the formation of an enzyme substrate complex which accounts for high specificity of enzyme catalysed reactions.

3. Once the proper orientation is attained the substrate molecules reacts to form the product in two steps.

4. Since product molecule do not have any affinity for the enzyme they leave the enzyme surface making room for fresh substrate.

Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-4

step 1: Formation of enzyme – substrate complex
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-5
Step 2: Dissociation of enzyme – substrate complex to form product
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-6
The rate of the formation of product depends upon concentration of ES.

Question 14.
What do ou mean by activity and selectivity of catalyst?
Answer:
1. Activity of Catalyst:
The activity ofcatalyst is its ability to increase the rate ofa particular reaction, Chemisorption is the main factor in deciding the activity of a catalyst. The adsorption of reactants in the catalyst surface should be neither too strong nor too weak. It should just be strong enough to make the catalyst active.

2. Selectivity of the catalyst:
The ability of the catalyst to dircct a reaction to yield a particular product is referred to as the selectivity of the catalyst. For example, by using different catalysts, we can get different products for the reaction between H2 and CO.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-7

Question 15.
Describe some feature of catalysis b Zeoliles.
Answer:
1. Zeolites are microporous, crystalline, hydrated aluminosilicates, made of silicon and aluminium tetrahedra.

2. There are about 50 natural zeolites and 1 50 synthetic zeolites. As silicon is tetravalent and aluminium is trivalent, the zeolite matrix carries extra negative charge. To balance the negative charge, there are extra framework cations for example, H+ or Na+ ions.

3. Zeolites earring protons are used as solid acids, catalysis and they are extensively used in the petrochemical industry for cracking heavy hydrocarbon fractions into gasoline, diesel,etc.

4. Zeolites earring Na ions are used as basic catalysis.

5. One of the most important applications of zeolites is their shape selectivity. In zeolites, the active sites namely protons are lying inside their pores. So, reactions occur only inside the pores of zeolites.

Question 16.
Give three uses of emulsions.
Answer:

  1. The cleansing action of soap is due to emulsions.
  2. It is used in the preparation of vanishing cream.
  3. It is used in the preparation of cold liver oil.

Question 17.
Why does bleeding stop by rubbing moist alum
Answer:
Blood is a colloidal sol. When we nib the injured part with moist alum then coagulation of blood takes place. Hence main reason is coagulation, which stops the bleeding. Therefore bleeding stop by rubbing moist alum.

Question 18.
Why is desorption important for a substance to act as good catalyst?
Answer:
Desorption is important for a substance to act as a good catalyst, so that after the reaction, the products found on the surface separate out (desorbed) to create free surface again for other reactant molecules to approach the surface and react. If desorption does not occur then other reactants are left with no space on the catalysts surface for adsorption and reaction will stop.

Question 19.
Comment on the statement: Colloid is not a substance but it is a state of substance.
Answer:
The statement is true. Because the same substance may exist as a colloid under certain conditions and as a crystalloid under certain other conditions. For example. NaCl in water behaves as a crystalloid while in benzene, it behaves as a colloid. Similarly, dilute soap solution behaves

like a crystalloid while concentrated solutions behaves as a colloid. It is the size of the particles which matters. That is the state in which the substance exists. If the size of the particles lies in the range 1 nm to 1oo nm, it is in the colloidal state.

Question 20.
Explain any one method for coagulation
Answer:
The flocculation and setting down of the sol particles is called coagulation. Various method of coagulation are given below:

  1. Addition of electrolytes
  2. Electrophoresis
  3. Mining oppositively charged sols
  4. Boiling.

Addition of electrolytes
A negative ion causes the precipitation of positively charged sol and vice versa. When the valency of ion is high, the precipitation power is increased. For example, the precipitation power of some cations and anions varies in the following order
Al3+ > Ba2+ > Na+, Similarly [Fe(CN)6]-3 > SO4-2 > Cl
The precipitation power of electrolyte is determined by finding the minimum concentration (millimoles / lit) required to cause precipitation of a sol in 2hours. This value is called flocculation value. The smaller the flocculation value greater will be precipitation.

Question 21.
Write a note on electro osmosis
Answer:
Electro osmosis:
A sol is electrically neutral. Hence the medium carries an equal but opposite charge to that of dispersed particles. When sol particles are prevented from moving, under the influence of electric field the medium moves in a direction opposite to that of the sol particles. This movement of dispersion medium under the influence of electric potential is called electro osmosis.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-8

Question 22.
Write a note on catalytic poison
Answer:
Catalytic poison:
Certain substances when added to a catalysed reaction, decreases or completely destroys the activity of catalyst and they are often known as catalytic poisons. For example, In the reaction,
2SO2 + O2 → 2SO3 with a Pt catalyst, the poison is AS2O3.
i.e., AS2O3 destroys the activity of pt. AS2O3 blocks the activity of the catalyst. So, the activity is lost.

Question 23.
Explain intermediate compound formation theory of catalysis with an example.
Answer:
The intermediate compound formation theory:
A catalyst acts by providing a new path with low energy of activation. in homogeneous catalysed reactions a catalyst may combine with one or more reactant to form an intermediate which reacts with other reactant or decompose to give products and the catalyst is regenerated.

Consider the reactions:
A + B → AB ……………(1)
A + C → AC (intermediate) ………….(2)
C is the catalyst
AC + B → AB + C …………(3)
Activation energies for the reactions (2) and (3) are lowered compared to that of (1). Hence the formation and decomposition of the intermediate accelerate the rate of the reaction.
Example:
The mechanIsm of Fridel crafts reaction is given below
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-9
The action of catalyst is explained as follows .
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-10

This theory describes,

  1. The specificity of a catalyst.
  2. The increase in the rate of the reaction with increase in the concentration of a catalyst.

Limitations

  1. The intermediate compound theory fails to explain the action of catalytic poison and activators (promoters).
  2. This theory is unable to explain the mechanism of heterogeneous catalysed reactions.

Question 24.
What is the difference between homogenous and hetrogenous catalysis?
Answer:
Hornogenous Catalysis:

  1. In a catalysed reaction the reactants, products and catalyst are present in the same phase.
  2. For example.
    Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-11
    Hence NO act as catalyst.
  3. Homogeneous catalysis explained by intermediate compound formation theory.

Heterogeneous Catalysis:

  1. In a reaction, the catalyst is present in a different phase. i.e., catalyst is not present in the same phase as that of reactants and products.
  2. For example.
    Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-12
    Hence Pt(s) act as catalyst.
  3. Hetenogeneous catalysis explained by adsorption theory.

Question 25.
Describe adsorption theory of catalysis.
Answer:
Adsorption theory:
Langmuir explained the action of catalyst in heterogeneous catalysed reactions based on adsorption. The reactant molecules are adsorbed on the catalyst surfaces, so this can also he called as contaçt catalysis.

According to this theory, the reactants arc adsorbed on the catalyst surface to form an activated complex which subsequently decomposes and gives the product. The various steps involved in a heterogeneous catalysed rcacton arc given as follows:

  1. Reactant molecules diffuse from bulk to the catalyst surface.
  2. The reactant molecules are adsorbed on the surface of the catalyst.
  3. The adsorbed reactant molecules are activated and form activated complex which is decomposed to form the products.
  4. The product molecules are desorbed.
  5. The product diffuse away from the surface of the catalyst.

Advantages of adsorption theory:
The adsorption theory explains the following .
1. Increase in the activity of a catalyst by increasing the surface area. Increase in the surface area of metals and metal oxides by reducing the particle size increases the rate of the reaction.

2. The action of catalytic poison occurs when the poison blocks the active centres of the catalyst.

3. A promoter or activator increases the number of active centres on the surfaces.

Samacheer Kalvi 12th Chemistry Surface Chemistry Additional Questions

Samacheer Kalvi 12th Chemistry Surface Chemistry 1 mark Questions and Answers

I. Choose the correct answer and write it. Answers are in bold it.

Question 1.
Which one of the following is used to absorb colourants from sugar?
(a) Silica gel
(b) Magnesia
(c) Charcoal
(d) Alumina
Answer:
(c) Charcoal

Question 2.
Silica gel is usually adsorb ………….
(a) Colourants
(b) Hydrogen
(c) Liquid Helium
(d) Water
Answer:
(d) Water

Question 3.
Which one of the following is called adsorbate?
(a) Charcoal
(b) Silica gel
(c) Ammonia
(d) Magnesia
Answer:
(c) Ammonia

Question 4.
Which of the following can act as adsorbent?
(a) Silica gel
(b) Ammonia
(c) Colourants
(d) Water
Answer:
(a) Silica gel

Question 5.
The surface of separation of two phases where the concentration of adsorbed molecule is high is known as …………..
(a) adsorbate
(b) adsorbent
(c) interface
(d) residual phase
Answer:
(c) interface

Question 6.
Consider the following statement.
(i) High adsorption is the result of high surface area of the adsorbent.
(ii) The process of removing an adsorbed substance is called absorption.
(iii) Adsorbed substance is called an adsorbate.

Which of the above statement is / are not correct?
(a) (i) & (ii)
(b) (ii) & (iii)
(c) (ii) only
(d) (iii) only
Answer:
(c) (ii) only

Question 7.
Which metal cannot act as adsorbent?
(a) Pt
(b) Ag
(c) Pd
(d) Al
Answer:
(d) Al

Question 8.
Consider the following statements.
(i) Adsorption is spontaneous process.
(ii) Adsorption is always accompanied by increase in free energy.
(iii) Adsorption is an endothermic reaction.

Which of the above statement is / are not correct?
(a) (i) only
(b) (ii) & (iii)
(c) (ii) & (i)
(d) (i) only
Answer:
(b) (ii) & (iii)

Question 9.
Absorption and adsorption if simultaneously occurs, it is called ……………
(a) occlusion
(b) sorption
(c) desorption
(d) dissolution
Answer:
(b) sorption

Questioin 10.
The process of sorption of gases on metal surface is called ……………
(a) Desorption
(b) Dissolution
(c) Occlusion
(d) Condensation
Answer:
(c) Occlusion

Question 11.
When gas molecules are held to the surface by the formation of chemical bond the heat energy released is nearly equal to
(a) 40 kJ/mole
(b) 800 kJ/mole
(c) 400 kJ/mole
(d) 4 kJ/mole
Answer:
(c) 400 kJ/mole

Question 12.
Which of the following is physical adsorption?
(a) Adsorption of H2 on nickel
(b) Friedel crafts reaction
(c) Synthesis of SO3 in the presence of NO
(d) Corrosion of iron
Answer:
(a) Adsorption of H2 on nickel

Question 13.
Which one of the following is chemical adsorption?
(a) Adsorption of O2 on tungsten
(b) Adsorption of ethyl alcohol vapours on nickel
(c) Adsorption of N2 on mica
(d) Rusting of iron
Answer:
(d) Rusting of iron

Question 14.
Which of the following occurs at low temperature?
(a) Adsorption of O2 on tun gsen
(b) Adsorption of N2 on mica
(c) Adsorption of ethyl alcohol vapours on nickel
(d) Adsorption of H2 on nickel
Answer:
(b) Adsorption of N2 on mica

Question 15.
Consider the following statements:
(i) Chemical adsorption is an instantaneous process
(ii) Multilayer of the adsorbate is formed on the adsorbent
(iii) Chemisorption involves the formation of activated complex.

Which of the above statement is / are not correct?
(a) (i) & (ii)
(b) (iii) only
(c) (i) only
(d) (ii) only
Answer:
(a) (i) & (ii)

Question 16.
Consider the following statements:
(i) In chemisorption, heat of adsorption is high
(ii) Monolayer of the adsorbate is formed during chemisorption
(iii) Physisorption increases with increase in temperature.

Which of the above statement is / are not correct’?
(a) (i) & (ii)
(b) (iii) only
(c) (ii) only
(d) (i) only
Answer:
(b) (iii) only

Question 17.
The extent of surface adsorption does not depend on
(a) Nature of the adsorbent
(b) Pressure
(c) Temperature
(d) Density
Answer:
(d) Density

Question 18.
Which of the following gases is not a permanent gas?
(a) NH3
(b) H2
(c) N2
(d) O2
Answer:
(a) NH3

Question 19.
Which of the following is liquefiable gas?
(a) SO2
(b) H2
(c) N2
(d) O2
Answer:
(a) SO2

Question 20.
Which one of the following is a permanent gas?
(a) NH3
(b) SO3
(c) N2
(d) CO2
Answer:
(c) N2

Question 21.
Consider the following statements.
(i) When pressure increases, the amount of physisorplion also increases.
(ii) Permanent gases like H2, N2 and O2 cannot be liquefied easily.
(iii) Lesser is the surface area, higher is the amount adsorbed.

Which of the above statement is / are correct?
(a) (i) & (ii)
(b) (iii) only
(c) (ii) only
(d) (i) only
Answer:
(a) (i) & (ii)

Question 22.
Which one of the following is used in blast furnace for drying air?
(a) Activated charcoal
(b) Silica gel
(c) Alumina
(d) Permutit
Answer:
(b) Silica gel

Question 23.
Which is employed in the softening of hardwater to absorb Ca2+ and Mg2+ ions?
(a) Alumina
(b) Silica gel
(c) Permutit
(d) Charcoal
Answer:
(c) Permutit

Question 24.
The formula for permutit is …………
(a) Ca Al2 Si4 O12
(b) CaAl3SiO2. xH2O
(c) Na2 Al2 Si4 O12
(d) Na2 SiO3
Answer:
(c) Na2 Al2 Si4 O12

Question 25.
Which one of the following is used to regenerate permutit in softening of hard water?
(a) Common salt
(b) Baking soda
(c) Washing soda
(d) Quick lime
Answer:
(a) Common salt

Question 26.
Which of the following is used to demineralise water?
(a) Permutit
(b) Common salt
(c) Ion exchange resin
(d) Charcoal

Question 27.
Which of the following is used during world war as gas masks?
(a) Permutit
(b) Silica gel
(c) Fuller’s earth
(d) Charcoal
Answer:
(d) Charcoal

Question 28.
Which of the following is used in petroleum refining and refining of vegetable oils?
(a) Charcoal
(b) Silica gel
(c) Pcrmutit
(d) Nickel
Answer:
(b) Silica gel

Question 29.
The catalyst used in the hydrogenation of oils to obtain vanaspathi is …………
(a) Iron
(b) Molybdenum
(c) Nickel
(d) Copper
Answer:
(c) Nickel

Question 30.
The catalyst and promoter used in Haber’s process are respectively ………..
(a) Mo, Fe
(b) Fe, Mo
(c) Pt, H2S
(d) Pt, V2O5
Answer:
(b) Fe, Mo

Question 31.
Which method is used for identification, detection and estimation of many substances even if they are in micro quantities?
(a) Lassaigne’s test
(b) Canus method
(c) Kjeldhals method
(d) Chromatography
Answer:
(d) Chromatography

Question 32.
Which one of the following is used in the identification of Al3+ ion in Al(OH)3?
(a) Red litmus
(b) Blue litmus
(c) Phenol red
(d) Sodium hydroxide
Answer:
(b) Blue litmus

Question 33.
Which ores are concentrated by froth floatation process?
(a) Oxide ore
(b) Carbonate ore
(c) Sulphate ores
(d) Suiphide ores
Answer:
(d) Suiphide ores

Question 34.
In froth floatation process, the lighter ore particles are wetted by …………..
(a) Olive oil
(b) Pine oil
(c) Soap oil
(d) Neem oil
Answer:
(b) Pine oil

Question 35.
Which one of the following is an example for homogeneous catalysis?
(a) Decomposition of acetaldehyde by 12 catalysts
(b) Hydrolysis of cane sugar with mineral acid
(c) Ester hydrolysis with alkali
(d) All the above
Answer:
(d) All the above

Question 36.
Which one of the following is an example for homogeneous catalysis?
(a) Manufacture of sulphuric acid by contact process
(b) Manufacture of ammonia by Haber’s process
(c) Oxidation of ammonia carried out in the presence of platinum gauze
(d) Hydrolysis of cane sugar with mineral acid
Answer:
(d) Hydrolysis of cane sugar with mineral acid

Question 37.
Which one of the following is an example for heterogeneous catalysis?
(a) Decomposition of acetaldehyde by I2 catalyst
(b) Decomposition of H2O2 in the presence of Pt catalyst
(c) Acid hydrolysis of ester
(d) Hydrolysis of cane sugar with mineral acid
Answer:
(b) Decomposition of H2O2 in the presence of Pt catalyst

Question 38.
Which one of the following is not an example for homogeneous catalysis?
(a) Contact process of manufacture of H2SO4
(b) Haber’s process of manufacture of NH3
(c) Acid hydrolysis of ester
(d) Freidel crafts reaction
Answer:
(c) Acid hydrolysis of ester

Question 39.
Consider the following statements:
(i) A catalyst needed in very small quantity
(ii) A catalyst can initiate a reaction
(iii) Catalyst are highly specific in nature

Which of the above statement is / are not correct?
(a) (i) & (iii)
(b) (ii) & (iii)
(c) (iii) only
(d) (ii) only
Answer:
(d) (ii) only

Question 40.
Consider the following statements.
(i) A solid catalyst will be more effective if it is taken in a finely divided form
(ii) A catalyst cannot initiate a reaction
(iii) For a chemical reaction4 catalyst is needed in very large quantity

Which of the above statement is / are not correct?
(a) (i) & (ii)
(b) (ii) & (iii)
(c) (iii) only
(d) (i) & (iii)
Answer:
(a) (i) & (ii)

Question 41.
The catalyst poison in contact process of manufacture of SO3 is …………
(a) As2O3
(b) H2S
(c) CO
(d) As2S3
Answer:
(a) As2O3

Question 42.
In Haber’s process of manufacture of ammonia, the Fe catalyst is poisoned by the pressure of …………….
(a) Mo
(b) Co
(c) H2S
(d) As2O3
Answer:
(c) H2S

Question 43.
In the reaction 2H2 + O2 → 2H2O acts as a catalytic poison for Pt catalyst.
(a) Co
(b) Mo
(c) As2O3
(d) H2S
Answer:
(a) Co

Question 44.
The negative catalyst in the decomposition of H2O2 is …………..
(a) Ethanol
(b) Acetic acid
(c) Ethanoic acid
(d) Methanol
Answer:
(a) Ethanol

Question 45.
Which one of the following is an example tar an autocalalysis?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-13

Question 46.
In the decomposition of hydrogen peroxide which acts as a negative catalyst?
(a) Dilute acid
(b) Glycerol
(c) a (or) b
(d) Ethanol
Answer:
(c) a (or) b

Question 47.
The energy required for the reactants to reach the activated complex is called …………
(a) threshold energy
(b) activation energy
(c) internal energy
(d) Gibbs free energy
Answer:
(b) activation energy

Question 48.
Which of the following is explained by intermediate compound formation theory?
(a) Mechanism of friedel crafts reaction
(b) Thermal decomposition of KClO3 in the presence of MnO2
(c) Oxidation of HCl by air in the presence of CuCl2
(d) Manufacture of NH3 by Haber’s process
Answer:
(d) Manufacture of NH3 by Haber’s process

Question 49.
Consider the following statements.
(i) Intermediate compound theory describes the specificity of a catalyst.
(ii) Intermediate compound theory explains the action of catalytic poison and activators.
(iii) Intermediate compound theory is unable to explain the mechanism of heterogeneous catalysed reactions.

Which of the above statement is / are not correct?
(a) (ii) only
(b) (i) & (iii)
(c) (iii) only
(d) (i) & (ii)
Answer:
(a) (ii) only

Question 50.
Who explained the action of catalyst in adsorption theory?
(a) Berzellius
(b) Langmuir
(c) Thomas Graham
(d) Dalton
Answer:
(b) Langmuir

Question 51.
Consider the following statements.
(i) The action of catalytic poison occurs when the poison blocks the active centres of the catalyst.
(ii) A promoter decreases the number of active centres on the surfaces.
(iii) Increase in the activity of a catalyst by increasing the surface area.

Which of the above statement is / are correct?
(a) (ii) only
(b) (iii) only
(c) (i) & (iii)
(d) (ii) & (iii)
Answer:
(c) (i) & (iii)

Question 52.
Which of the following catalyse the chemical reaction in living organism?
(a) enzymes
(b) protein
(c) lipids
(d) serum
Answer:
(c) lipids

Question 53.
Which of the following enzyme catalyse the hydrolysis of starch into maltose?
(a) maltase
(b) irivertase
(c) diastase
(d) zymase
Answer:
(c) diastase

Question 54.
Which enzyme catalyses the conversion of glucose into ethanol?
(a) maltase
(b) invertase
(c) diastase
(d) zymase
Answer:
(c) diastase

Question 55.
Which of the following act as catalyst in the oxidation of alcohol into acetic acid?
(a) pepsin
(b) diastase
(c) micoderma
(d) urease
Answer:
(c) micoderma

Question 56.
Which catalyst is used in the hydrolysis of urea?
(a) micoderma
(b) zymase
(c) pepsin
(d) urease
Answer:
(d) urease

Question 57.
Which of the following enzyme is present in soya beans?
(a) urease
(b) zymase
(c) pepsin
(d) lactase
Answer:
(a) urease

Question 58.
Consider the following statements.
(i) Enzymes are complex protein molecules with three dimensional structures.
(ii) Enzymes catalyse the chemical reaction in living organism.
(iii) Enzymes arc not specific in catalytic action.

Which of the above statement is J are correct?
(a) (iii) only
(b) (ii) & (iii)
(c) (i) & (ii)
(d) (i) & (iii)
Answer:
(c) (i) & (ii)

Question 59.
Consider the following statements.
(i) Enzyme catalysed reaction has maximum rate at optimum temperature
(ii) Enzyme catalysis is highly specific in nature
(iii) Catalytic activity of enzyme is decreased by coenzyrnes or activators.

Which of the above statement is / are not correct?
(a) (iii) only
(b) (i) only
(c) (ii) only
(d) (i) & (ii)

Question 60.
The temperature at which enzyme activity is high (or) maximum is called ………….
(a) critical temperature
(b) optimum temperature
(c) low temperature
(d) high temperature
Answer:
(b) optimum temperature

Question 61.
Enzymes can be active in human body at a temperature of ………….
(a) 98°F
(b) 105°F
(c) 37°F
(d) 50°F
Answer:
(a) 98°F

Question 62.
Consider the following statements.
(i) Zeolites are alumino silicates made of silicon and aluminium tetrahedra.
(ii) Zeolites carrying Na ions are used as basic catalyst.
(iii) As silicon is tetravalent and aluminium is trivalent, the zeolite matrix carries extra positive charge.

Which of the above statement is / are correct?
(a) (i) & (ii)
(b) (i), (ii) & (iii)
(c) (iii) only
(d) (ii) only
Answer:
(a) (i) & (ii)

Question 63.
Which one of the following is used in petrochemical industry for cracking heavy hydrocarbon fractions into gasoline, diesel etc.?
(a) permutit
(b) zeolite
(c) pepsin
(d) protein
Answer:
(b) zeolite

Question 64.
Which one of the following is used as a catalyst in the conversion of Lindane to cyclohexane?
(a) Fe°/Pd°
(b) Ni
(c) Zn + HCl
(d) LiAIH4
Answer:
(a) Fe°/Pd°

Question 65.
Which one of the following is used as catalyst in homogeneous and heterogeneous catalysis?
(a) enzymes
(b) zeolite
(c) nano catalyst
(d) coenzyme
Answer:
(c) nano catalyst

Question 66.
Who studied and analysed about colloids?
(a) Berzelius
(b) Thomas Graham
(c) Langmuir
(d) Robert Brown
Answer:
(b) Thomas Graham

Question 67.
Which one of the following is lyophillic colloid?
(a) Protein sol
(b) Gold sol
(c) Silver sol
(d) Platinum sol
Answer:
(a) Protein sol

Question 68.
Which one of the following is lyophobic colloid?
(a) Protein sol
(b) Starch sol
(c) Gel
(d) Gold sol
Answer:
(d) Gold sol

Question 69.
An example of liquid aerosol is ………..
(a) Soda water
(b) Milk
(c) Fog
(d) Inks
Answer:
(c) Fog

Question 70.
Which of the following is an example of Emulsion?
(a) mayonnaise
(b) shaving cream
(c) fumes
(d) paint
Answer:
(a) mayonnaise

Question 71.
The dispersed phase and dispersion medium in smoke, fumes and dust are …………..
(a) gas, solid
(b) solid, gas
(c) gas, liquid
(d) solid, liquid
Answer:
(b) solid, gas

Question 72.
Inks, paints arc considered as …………
(a) liquid in solid
(b) solid in liquid
(c) gas in gas
(d) solid in solid
Answer:
(b) solid in liquid

Question 73.
Which of the following is an example for gel?
(a) Pumice stone
(b) Pearls
(c) Coloured glass
(d) Butter
Answer:
(c) Coloured glass

Question 74.
Which one of the following is an example for solid sol?
(a) Butter
(b) Cheese
(c) Pearls
(d) Pumice stone
Answer:
(c) Pearls

Question 75.
Soda water is an example for ………..
(a) gel
(b) emulsion
(c) foam
(d) sol
Answer:
(c) foam

Question 76.
Colloidal ink and graphite are prepared by …………
(a) colloid mill
(b) Bredig’s arc
(c) ultrasonic homogenizer
(d) peptisation
Answer:
(a) colloid mill

Question 77.
Which method is used to prepare metal sols?
(a) ultrasonic dispersion
(b) mechanical dispersion
(c) Bredigs arc method
(d) peptisation
Answer:
(c) Bredigs arc method

Question 78.
Who prepared non aqueous inflammable liquids like Benzene and ether by Bredig’s arc method?
(a) George Bredig
(b) Sved berg
(c) Thomas Graham
(d) Robert Brown
Answer:
(b) Sved berg

Question 79.
Which method is used to prepare mercury colloid?
(a) peptisation
(b) mechanical dispersion
(c) ultrasonic dispersion
(d) Bredig’s arc method
Answer:
(c) ultrasonic dispersion

Question 80.
Mercury sol is obtained by subjecting it to sound waves of frequency more than ………..
(a) 20 Hz
(b) 20 kHz
(c) 200 kHz
(d) 2000 kHz
Answer:
(b) 20 kHz

Question 81.
The conversion of a precipitate into colloid is called …………..
(a) coagulation
(b) hydrolysis
(c) condensation
(d) peptisation
Answer:
(d) peptisation

Question 82.
Gold sol is prepared by reduction of auric chloride using …………..
(a) water
(b) HCHO
(c) CH3CHO
(d) CH3COOH
Answer:
(b) HCHO

Question 83.
Which method is suitable to prepare I2 sol and Se sol?
(a) Reduction
(b) Hydrolysis
(c) oxidation
(d) peptisation
Answer:
(c) oxidation

Question 84.
Which condensation method is used to prepare sulphur sol?
(a) Hydrolysis
(b) Decomposition
(c) Reduction
(d) Peptisation
Answer:
(b) Decomposition

Question 85.
Arsenic sulphide colloid is prepared by ………..
(a) hydrolysis
(b) reduction
(c) double decomposition
(d) decomposition
Answer:
(c) double decomposition

Question 86.
By which method phosphorous colloid can be prepared’?
(a) Decomposition
(b) Exchange of solvent
(c) Hydrolysis
(d) Reduction
Answer:
(b) Exchange of solvent

Question 87.
Which one of the following is not used to purify colloids?
(a) Dialysis
(b) Peptisation
(c) Electro dialysis
(d) Uhrafilteration
Answer:
(b) Peptisation

Question 88.
The process of conversion of colloidal solution into precipitate is known as …………..
(a) peptisation
(b) dispersion
(c) coagulation
(d) decomposition
Answer:
(c) coagulation

Question 89.
Which one of the following is named collodion?
(a) 4% solution of nitro cellulose in a mixture of alcohol and water
(b) 40% solution of cellulose acetate in acetic acid.
(c) agar-agar along with gel
(d) semipermeable membrane
Answer:
(a) 4% solution of nitro cellulose in a mixture of alcohol and water

Question 90.
Which of the following is the size of the colloidal particle?
(a) 100 μm diameter – 1000 μm diameter
(b) 1 mμ to 1 μm diameter
(c) 1 mμ to 100 μm diameter
(d) 1 μm to 1 μm diameter
Answer:
(b) 1 mμ to 1 μm diameter

Question 91.
Consider the following statements.
(i) Colloidal solutions are quite stable and are not affected by gravity
(ii) Colloids diffuse more readily through membranes
(iii) Colloidal solutions show colligative properties

Which of the above statement is / are correct?
(a) (i) & (iii)
(b) (ii) & (iii)
(c) (ii) only
(d) (iii) only
Answer:
(a) (i) & (iii)

Question 92.
The shape of tungstic acid W3O5 sol is ………….
(a) spherical
(b) disc
(c) plate like
(d) rod like
Answer:
(d) rod like

Question 93.
Which one of the following colloid has spherical shape?
(a) AS2S3
(b) Fe(OH)3
(c) W3O5
(d) dust
Answer:
(a) AS2S3

Question 94.
Tyndall effect is possible in colloid due to ……………
(a) absorption of light
(b) adsorption of light
(c) scattering of light
(d) reflection of light
Answer:
(c) scattering of light

Question 95.
Which one of the following does not show Tyndali effect and Brownian movement?
(a) Milk
(b) common salt solution
(c) smoke
(d) tungstic acid sol
Answer:
(b) common salt solution

Question 96.
The migration of sol particles under the influence of electric field is called ……………
(a) electro osmosis
(b) electro dialysis
(c) electrophoresis
(d) dialysis
Answer:
(c) electrophoresis

Question 97.
Which one of the following is used for detection of pressure of charge on sol particles?
(a) Cataphoresis
(b) Electro dialysis
(c) Dialysis
(d) Ultrafilteration
Answer:
(a) Cataphoresis

Question 98.
Which of the following is positively charged colloid?
(a) haemoglobin
(b) starch
(c) clay
(d) AS2S3
Answer:
(a) haemoglobin

Question 99.
Which one of the following is a positively charged colloid?
(a) Ag
(b) AU
(c) Basic dyes
(d) Clay
Answer:
(c) Basic dyes

Question 100.
Which one of the following is a negatively charged colloid?
(a) Pt
(b) Al(OH)3
(c) Fe (OH)3
(d) Basic dyes
Answer:
(a) Pt

Question 101.
Which one of the following is a negatively charged colloid?
(a) Ferric hydroxide
(b) Clay
(c) Basic dyes
(d) Haemoglobin
Answer:
(b) Clay

Question 102.
The movement of dispersion medium under the influence of electric potential is called ………….
(a) Electrophoresis
(b) Cataphoresis
(c) Electro osmosis
(d) Electro dialysis
Answer:
(c) Electro osmosis

Question 103.
Which one of the following is added to gold sol to protect it?
(a) Gelatine sol
(b) Gum
(c) Starch
(d) Basic dye
Answer:
(a) Gelatine sol

Question 104.
Consider the following statements.
(i) Smaller the gold number, greater the protective power
(ii) Greater the gold number, greater the protective power
(iii) Colloidal sols with opposite charges are mixed, mutual coagulation takes place.

Which of the above statement is / are not correct?
(a) (i) only
(b) (i) & (iii)
(c) (ii) only
(d) (ii) & (iii)
Answer:
(c) (ii) only

Question 105.
Which one of the following can act as emulsifier?
(a) glue
(b) dye
(c) water
(d) starch
Answer:
(a) glue

Question 106.
Which one of the following is not used to identify the types of emulsion?
(a) dye test
(b) viscosity test
(c) conductivity test
(d) Tollen’s test
Answer:
(d) Tollen’s test

Question 107.
By adding which one of the following oil in water emulsion containing potassium soap can be converted into water in oil emulsion?
(a) MCl3
(b) NaCI
(c) KCI
(d) C6H5Cl
Answer:
(a) MCl3

Question 108.
Which of the following colloid is used as a medicine for stomach troubles?
(a) colloidal Au
(b) colloidal Ca
(c) milk of magnesia
(d) silver sol
Answer:
(c) milk of magnesia

Question 109.
Which one of the following is used in the purification of drinking water?
(a) silver sol protected by gelatine
(b) milk of magnesia
(c) Alum containing Al3+
(d) Argyrol
Answer:
(c) Alum containing Al3+

Question 110.
Which of the following is used as tonics?
(a) milk of magnesia
(b) Argyrol
(c) colloidal Au & colloidal Ca
(d) Alum
Answer:
(c) colloidal Au & colloidal Ca

Question 111.
Which one of the following is used in tanning of leather?
(a) chromium salt
(b) colloidal Au
(c) Argyrol
(d) Fe (OH)3
Answer:
(a) chromium salt

Question 112.
Carbon dust in air is solidified by ………..
(a) cottrell’s precipitator
(b) colloidal mill
(c) Bredig’s arc
(d) peptisation
Answer:
(a) cottrell’s precipitator

Question 113.
Which of the following voltage is used in cottrell’s precipitator?
(a) 5000 V
(b) 50,000 V
(c) 1,000V
(d) 10,000V
Answer:
(b) 50,000 V

Question 114.
The blue colour of the sky is due to …………
(a) coagulation
(b) peptisation
(c) Tyndall effect
(d) Brownian movement
Answer:
(c) Tyndall effect

Question 115.
Which one of the following is used to distinguish Natural honey and artificial honey?
(a) Ammoniacal AgNO3
(b) Fehling’s solution
(c) Arsenic suiphide sol
(d) gelatin
Answer:
(a) Ammoniacal AgNO3

Question 116.
Which one of the following is the catalyst poison in Haber’s process?
(a) AS2S3
(b) AS2O3
(c) Co
(d) H2S
Answer:
(d) H2S

Question 117.
Which one of the following is an example for water in oil emulsion?
(a) Milk
(b) Vanishing cream
(c) Butter
(d) Soap
Answer:
(c) Butter

Question 118.
Which of the following is contributed towards the extra stability of lyophillic colloid?
(a) Hydration
(b) Charge
(c) Colour
(d) Tyndall effect
Answer:
(a) Hydration

Question 119.
A catalyst is a substance which
(a) increases the equilibrium concentration of the product
(b) changes the equilibrium constant of the reaction
(c) shortens the time to reach equilibrium
(d) supplies energy to the reaction
Answer:
(c) shortens the time to reach equilibrium

Question 120.
The ability of an ion to bring about coagulation of a given colloid depends upon …………
(a) its size
(b) magnitude of its charge
(c) the sign of its charge
(d) both the magnitude and sign of the charge
Answer:
(d) both the magnitude and sign of the charge

Question 121.
Which one of the following is an incorrect statement for physisorption?
(a) It is a reversible process
(b) It requires less heat of adsorption
(c) It requires activation energy
(d) It take place at low temperature
Answer:
(c) It requires activation energy

Question 122.
Which is not a colloid?
(a) Chlorophyll
(b) Egg
(c) Ruby glass
(d) Milk
Answer:
(a) Chlorophyll

Question 123.
Which of the following electrolytes is most effective in the coagulation of gold sol?
(a) NaNO3
(b) K4[Fe(CN)6]
(c) Na3PO4
(d) MgCl2
Answer:
(b) K4[Fe(CN)6]

Question 124.
Gold number gives ………………..
(a) the amount of gold present in the colloid
(b) the amount of gold required to break the colloid
(c) the amount of gold required to protect the colloid
(d) the measure of protective power of a lyophillic colloid
Answer:
(d) the measure of protective power of a lyophillic colloid

Question 125.
Identify the gas which is readily adsorbed by activated charcoal?
(a) N2
(b) SO2
(c) H2
(d) O2
Answer:
(b) SO2

Question 126.
Starch dispersed in hot water is an example of …………..
(a) emulsion
(b) hydrophobic sol
(c) lyophilic sol
(d) associated colloid
Answer:
(c) lyophilic sol

Question 127.
Which one is an example of gel?
(a) soap
(b) cheese
(c) milk
(d) fog

Question 128.
The random, zig-zag motion of colloidal particles in the dispersion medium is referred to as …………..
(a) Electrophoresis
(b) Brownian movement
(c) Tyndall effect
(d) Electro osmosis
Answer:
(b) Brownian movement

Question 129.
Which of the following electrolytes is least effective in causing flocculation of ferric hydroxide sol?
(a) K4 [Fe(CN)6]
(b) K2CrO4
(c) KBr
(d) K2SO4
Answer:
(c) KBr

Question 130.
Gelatin is mostly used in making icecream in order to …………..
(a) prevent making of colloid
(b) to stabilize the colloid and to prevent the crystallization
(c) to stabilise the mixture
(d) to enrich the aroma
Answer:
(b) to stabilize the colloid and to prevent the crystallization

Question 131.
Which one of the following is not a colloidal solution?
(a) smoke
(b) ink
(c) air
(d) coffee
Answer:
(c) air

Question 132.
Milk can be preserved by adding a few drops of …………
(a) HCOOH
(b) HCHO
(c) CHCOOH
(d) CH3CHO
Answer:
(b) HCHO

Question 133.
Bleeding is stopped by the application of ferric chloride. This is because …………
(a) ferric chloride seal the blood cells
(b) blood starts flowing in ohter direction
(c) blood is coagulated and blood vessel is sealed
(d) blood is peptised
Answer:
(c) blood is coagulated and blood vessel is sealed

Question 134.
Delta at the rivers are formed due to …………
(a) peptisation
(b) coagulation
(c) hydrolysis
(d) precipitation
Answer:
(b) coagulation

Question 135.
Alum purifies muddy water by …………..
(a) dialysis
(b) adsorption
(c) coagulation
(d) forming a true solution
Answer:
(c) coagulation

Question 136.
Reactions of zeolite catalysts depend on ………….
(a) pores
(b) apertures
(c) size of cavily
(d) all of these
Answer:
(d) all of these

Question 137.
chemisorption ……………
(a) increases with increase in temperature
(b) decreases with increase in temperature
(c) remains unaffected by the, change of temperature
(d) first increases and then decreases.
Answer:
(d) first increases and then decreases.

Question 138.
Adsorption is always …………
(a) endothermic
(b) exothermic
(c) iso thermic
(d) either a (or) b
Answer:
(a) endothermic

Question 139.
Which one of the following can be explained by the adsorption theory?
(a) Homogeneous catalysis
(b) Acid-base catalysis
(c) Heterogeneous catalysis
(d) Enzyme catalysis
Answer:
(c) Heterogeneous catalysis

Question 140.
Physical adsorption is inversly proportional to ……………..
(a) volume
(b) concentration
(c) temperature
(d) all of these
Answer:
(c) temperature

Question 141.
Noble gases are adsorbed by ……………
(a) anhydrous CaCl2
(b) Fe(OH)3
(c) Conc. H2SO4
(d) activated charcoal
Answer:
(d) activated charcoal

Question 142.
Animal charcoal is used in decolourising agent in the manufacture of sugar because it is a good …………..
(a) adsorbate
(b) adsorbent
(c) oxidising agent
(d) dehydrating agent
Answer:
(a) adsorbate

Question 143.
Gold number is associated only with …………
(a) lyophobic colloids
(b) lyophilic colloids
(c) both lyophobic and lyophilic colloids
(d) Au in water
Answer:
(b) lyophilic colloids

Question 144.
Which of the following forms a colloidal solution with water?
(a) NaCl
(b) Glucose
(c) Starch
(d) Barium sulphate
Answer:
(c) Starch

Question 145.
Which one of the following is an example for homogeneous catalysis?
(a) Hydrogenation of oil
(b) manufacture of NH3 by Haber’s process
(c) manufacture of sulphuric acid by contact process
(d) hydrolysis of sucrose in the presence of dilute hydrochloric acid
Answer:
(d) hydrolysis of sucrose in the presence of dilute hydrochloric acid

Question 146.
Which of the following does not involve coagulation?
(a) peptisation
(b) formation of delta regions
(c) treatment of drinking water by potash alum
(d) clotting of blood by the use of ferric chloride
Answer:
(a) peptisation

Question 147.
Among the electrolytes Na2SO4, CaCI2, Al2(SO4)3 and NH4Cl, the most effective coagulating agent for Sb2S3 Sol is ……………
(a) Na,SO4
(b) CaCl2
(c) Al2(SO4)3
(d) NH4Cl
Answer:
(c) Al2(SO4)3

Question 148.
Which of the following statement is incorrect regarding physisorption?
(a) It occurs because of Van der Waals forces
(b) more easily liquefiable gases are adsorbed easily
(c) under high pressure, it resuLts into multimolecular layer on adsorbent surface
(d) enthalpy of adsorption is low and positive
Answer:
(d) enthalpy of adsorption is low and positive

Question 149.
Rate of physical adsorption increase with ………..
(a) increase in temperature
(b) decrease in pressure
(c) decrease in temperature
(d) decrease in surface are
Answer:
(c) decrease in temperature

Question 150.
Gold numbers of protective eolloids, A, B, C and D are respectively 0.50, 0.01, 0.10 and 0.005. The correct order of the stability of colloids is ……..
(a) B < D < A < C
(b) D < A < C < B
(c) C < B < D < A
(d) A < C < B < D
Answer:
(d) A < C < B < D

II. Fill in the blanks

  1. The surface of separation of the two phases where the concentration of adsorbed molecule is high is known as …………..
  2. In adsorption, if the concentration of a substance in the interface is high, it is called ……………
  3. The process of removing a adsorbed substance from the surface is called ……………
  4. Adsorption is always accompanied by decrease in ……………
  5. A term …………… is used for sorption of gases on metal surfaces
  6. M.C. Bain introduced a term …………… to represent the simultaneous adsorption and absorption.
  7. In chemical adsorption, gas molecules are held to the surface by formation of chemical bond and nearly …………… is given out as heat of adsorption
  8. In physical adsorption …………… exist between adsorbent and adsorbate
  9. Heat of adsorption is low hence physical adsorption occurs at ……………
  10. …………… involves the formation of activated complex with appreciable activation energy.
  11. Adsorption occurs at fixed sites called ……………
  12. Gases like NH3, SO3 and CO2 are …………… as have greater Van der Waals force of attraction.
  13. gases like H2, N2, O2 have low critical temperature and ………….. slowly
  14. A plot between the amount of adsorbate adsorbed and pressure or concentration of adsorbate at constant temperature is called …………..
  15. Freundlich adsorption isothermal equation is applicable fo adsorption of …………..
  16. During World War I ………….. gas mask was employed
  17. ………….. is used to create high vaccum in vessels.
  18. In blast furnace ………….. is used for drying air
  19. For dehydration and also purification of gases like CO2, N2, CI2, O2 and He ………….. and are employed.
  20. …………..is employed in the softening of hard water to adsorb Ca2+ and Mg2+ ions
  21. In the process of softening of hard water, exhausted permutit is regenerated by adding a solution of …………..
  22. ………….. are used to demineralise water.
  23. ………….. and ………….. are used in petroleum refining and refining of vegetable oil.
  24. ………….. is used to decolourising agent in manufacture of sugar from molasses.
  25. In forth floation process, the suiphide are particles are wetted by …………..
  26. ………….. is defined as a substance which alters the rate of a chemical reaction without itself undergoing chemical change.
  27. The decomposition of acetaldehyde by I2 catalyst is an example of ………….. catalysis.
  28. Manufacture of sulphuric acid by contact process is an example of ………….. catalysis.
  29. Friedel crafts reaction is an example of ………….. catalysis.
  30. The substances increases the activity of a catalyst are called …………..
  31. ………….. or ………….. used as promoter for iron in Haber’s process
  32. ………….. destroys the activity of platinum in contact process
  33. In the reaction CH3COOC2H5 + H2O → CH3COOH + C2H5OH ………….. is act as auto calyst.
  34. The decomposition of H2O2 rate is decreased by …………..
  35. As …………..is lowered in the presence of catalyst, more molecules take part in the reaction and hence the rate of the reaction increases.
  36. The mechanism of friedel crafts reaction is explained by ………….. theory.
  37. The catalyst used for the oxidation of HCl by air is …………..
  38. Thermal decomposition of KClO3 in the presence of ………….. follows ………….. theory.
  39. Intermediate compound formation theory is unable to explain the mechanism of …………..
  40. Hydrogenation of ethylene in the presence of nickel catalyst follows ………….. theory.
  41. ………….. are complex protein molecules and catalyse the chemical reaction in living organism.
  42. The enzyme ………….. hydrolyses starch into maltose.
  43. The enzyme ………….. oxidises alcohol into acetic acid.
  44. Enzyme catalysed reaction has ………….. rate at optimum temperature.
  45. ………….. in hibits the action of bacteria and used for curing pneumonia.
  46. ………….. are microporous, hydrated alumino silicates.
  47. Zeolites carrying ………….. are used as basic catalysts
  48. Like heterogeneous catalyst ………….. can be recovered and recycled.
  49. Sols of gold, silver, platinum and copper are examples of …………..
  50. So is of protein and starch are examples of …………..
  51. A liquid in liquid colloid is called …………..
  52. Pearls, opals and Ruby red glass are belong the colloid named …………..
  53. Rubber forns colloidal solution with …………..
  54. In colloid mill, the two metal plates rotating in opposite directions of nearly ………….. revolution per minute.
  55. Colloidal solutions of ink and graphite are prepared by ………….. method.
  56. A brown colloidal solution of platinum was prepared by ………….. in 1898.
  57. ………….. is added as an stabilising agent for making platinum colloid.
  58. Metal hydroxide is added as an ………….. for making noble metal sols.
  59. Claus obtained ………….. by subjecting ………….. to high frequency ultrasonic vibrations,
  60. In the preparation of AgCI colloid from AgCl precipitate, the peptising or dispersing agent used is …………..
  61. Gold sol is prepared by reduction of auric chloride using …………..
  62. Arsenic sulphide colloid can be prepared by ………….. method.
  63. 12 sol is obtained from HIO3 by ………….. method.
  64. The process of conversion of colloidal solution into precipitate is called …………..
  65. In the dialysis of kidney. recycling of patient’s blood is done through semipermeable tube in an ………….. solution
  66. Collodion is 4% solution of ………….. in a mixture of …………..
  67. The size of colloidal particles ranges from …………..
  68. The shape of blue gold sol (or) Fe(OH)3 sol is …………..
  69. Pollen grains suspended in water showed …………..
  70. The flocculation and setting down of sol particles is called …………..
  71. When the valency of ion is high ………….. power is increased in colloids.
  72. The smaller the ………….. value, greater will be precipitation of colloids.
  73. ………….. is added to gold sol to protect it.
  74. ………….. introduced the term gold number as a measure of protecting power of a colloid.
  75. An oil in watrer emulsion containing potassium soap as emulsifying agent can be converted into water in oild emulsion by adding ………….. or …………..
  76. Synthetic polymers like polystyrene, silicones and PVC, are …………..
  77. ………….. colloid is used as eye lotion.
  78. ………….. protected by gelatin is known as Argyrol.
  79. ………….. salts arc used in tanning of leather.
  80. Natural honey is distinguished artificial honey by adding …………..

Answer:

  1. interface
  2. positive adsorption
  3. desorption
  4. free energy
  5. occlusion
  6. sorption
  7. 400kJ/rnole
  8. Van der Waals forces of attraction
  9. low temperature
  10. Chemisorption
  11. active centres
  12. easily liquefiable
  13. Permanent, adsorbed
  14. Adsorption isotherm
  15. gases on solid surface
  16. charcoal
  17. Activated charcoal
  18. silica gel
  19. alumina, silica
  20. Permutit
  21. common salt
  22. Con exchange resins
  23. Fuller’s earth, silica gel
  24. Animal charcoal
  25. pine oil
  26. catalyst
  27. homogeneous
  28. heterogeneous
  29. heterogeneous
  30. promoters
  31. Mo (or) Al2O3
  32. AS2O3 catalyst poison
  33. CH3COOH
  34. ethanol (or) Glycerol, negative catalyst
  35. Activation energy
  36. intermediate compound formation
  37. CuCI2
  38. MnO2, intermediate compound formation theory
  39. heterogeneous catalysis
  40. adsorption
  41. enzymes
  42. diastase
  43. micoderma aceti
  44. maximum
  45. penicillin
  46. zeolites
  47. Na ions
  48. nano catalyst
  49. lyophobic sols (or) irreversible sols
  50. lyophilic sols (or) reversible sols
  51. emulsion
  52. solid sol
  53. benzene
  54. 7000
  55. mechanical dispersion
  56. George Bredig
  57. alkali hydroxide
  58. stabilising agent
  59. mercury sol, mercury
  60. HCl
  61. formaldehyde
  62. double decomposition
  63. oxidation
  64. coagulation
  65. isotonic saline
  66. nitro cellulose, alcohol and water
  67. 1 mi to llim diameter
  68. disc or plate like
  69. Brownian movement
  70. coagulation
  71. precipitation
  72. flocculation
  73. geLatine sol
  74. Zsigmondy
  75. CaCl2, AlCl3
  76. colloids
  77. Argyrol
  78. Silver sol
  79. chromium
  80. Tollens reagent (or) Ammoniacal AgNO3

III. Match the column I & II using the code given below the coulum.

Question 1.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-14
Answer:
(a) 4 3 1 2

Question 2.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-15
Answer:
(c) 3 4 1 2

Question 3.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-16
Answer:
(a) 4 3 1 2

Question 4.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-17
Answer:
(a) 2 3 4 1

Question 5.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-19
Answer:
(b) 3 4 2 1

Question 6.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-20
Answer:
(a) 3 1 4 2

Question 7.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-21
Answer:
(a) 4 1 2 3

Question 8.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-23
Answer:
(a) 4 3 2 1

Question 9.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-25
Answer:
(a) 2 4 1 3

Question 10.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-26
Answer:
(a) 4 3 1 2

Question 11.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-27
Answer:
(c) 3 1 4 2

Question 12.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-28
Answer:
(a) 4 3 1 2

Question 13.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-29
Answer:
(d) 3 1 4 2

Question 14.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-30
Answer:
(b) 4 3 2 1

Question 15.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-31
Answer:
(a) 2 4 1 3

Question 16.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-32
Answer:
(b) 3 4 2 1

Question 17.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-33
Answer:
(a) 4 1 2 3

Question 18.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-34
Answer:
(a) 3 1 4 2

IV. Assertion and Reason

Question 1.
Assertion (A) : Absorption is a bulk phenomenon.
Reason (R) : The absorbed molecules are distributed throughout the absorbent.
(a) Both A and R are correct and R is the correct explanation of A.
(b) A is correct but R is wrong.
(c) A is wrong but R is correct.
(d) Both A and R are wrong.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 2.
Assertion (A) : Adsorption is a spontaneous process.
Reason (R) : Adsorption is always accompanied by decrease in free energy. When molecules are adsorbed, there is always a decrease in randomness of the molecules.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not correct explanation of A.
(c) Both A and R are wrong.
(d) A is correct but R is wrong.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 3.
Assertion (A) : Chemical adsorption is an exothermic process.
Reason (R) : In chemical adsorption, gas molecules are held to the surface by formation of chemical bonds. Since strong bond is formed, nearly 400kJ/mole is given out as heat adsorption.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not correct explanation of A.
(c) Both A and R are wrong.
(d) A is correct but R is wrong.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 4.
Assertion (A) : Physical adsorption occurs at low temperature.
Reason (R) : ¡n physical adsorption, weak Van der Waals force of attraction exist. Other weak forces exist in physical adsorption are dipole-dipole interaction and dispersion forces. As these forces are weak, heat of adsorption is low.
(a) Both A and R are correct but R is not correct explanation of A.
(b) Both A and R are correct and R is the correct explanation of A.
(c) Both A and R are wrong.
(d) A is correct but R is wrong.
Answer:
(b) Both A and R are correct and R is the correct explanation of A.

Question 5.
Assertion (A) : Platinised asbestos is a better adsorbent than platinum block.
Reason (R) : Higher the surface area, higher is the amount adsorbed. In platinum coated asbestos the surface area is more and so it act as a better adsorbent.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are wrong.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 6.
Assertion (A) : Gases like SO2, NH3 and CO2 are readily adsorbed.
Reason (R) : SO2, NH3 and CO2 are easily liquefiable as have greater van der WaaI’s forces of attraction and adsorbed readily.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and Rare wrong.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 7.
Assertion (A) : Permanent gases like H2, N2 and O2 cannot be adsorbed readily.
Reason (R) : Permanent gases having low critical temperature and adsorbed slowly.
(a) Both A and R are wrong.
(b) A is correct and R is the correct explanation of A.
(c) A is wrong but R is correct.
(d) A is correct but R is wrong.
Answer:
(b) A is correct and R is the correct explanation of A

Question 8.
Assertion (A) : Chromatography is a very effective method and used for identification, detection and estimation of micro quantities of many substances.
Reason (R) : Chromatography technique is applied for separation and detection of components in a mixture it is mainly based on adsorption of components on the surface of adsorbents.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 9.
Assertion (A) : Ester hydrolysis of acid (or) alkali catalyst is an example of homogeneous catalysis.
Reason (R) : Ester, H2O acid (or) alkali and the products are in liquid form.
(a) Both A and R are correct but R is the correct explanation of A.
(b) Both A and R are wrong.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct,
Answer:
(a) Both A and R are correct but R is the correct explanation of A.

Question 10.
Assertion (A) : The manufacture of sulphuric acid by contact process is an example of heterogeneous catalysis.
Reason (R) : The catalyst Pt (or) VO5, reactants and products are in different phases in contact process.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not correct explanation of A.
(c) Both A and R are wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 11.
Assertion (A) : Acid hydrolysis of ethylacetate by water to produce acetic acid and ethanol is an example of auto catalysis.
Reason (R) : In acid hydrolysis of ester, the product acetic acid act as catalyst and this process is called autocatalysis.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are wrong.
(c) A is correct hut R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 12.
Assertion (A) : Effective and efficient conversion is the special characteristic of enzyme catalysed reactions.
Reason (R) : An enzyme may transform a million molecules of reactants to products in a minute.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not correct explanation of A.
(c) A is correct but R is wrong.
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 13.
Assertion (A) : lyophillic colloids will not get precipitated easily.
Reason (R) : In lyophillic colloids, definite attractive forces exists between dispersion medium and dispersed phase and they are more stable.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not correct explanation of A.
(c) Both A and R are wrong.
(d) A is correct but R is wrong.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 14.
Assertion (A) : Lyophobic colloids like sols of gold will precipitate readily.
Reason (R) : In lyophobic colloids, no attractive force exists between the dispersed phase and dispersion medium and are less stable.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not correct explanation of A.
(c) Both A and R are correct.
(d) A is correct but R is wrong.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 15.
AssertIon (A) : Iron colloid cannot be prepared by Bredig’s arc method.
Reason (R) : iron cannot react with alkali hydroxide stabilising agent added in water.
(a) Both A and R are correct and R is the correct explanation of A.
(b) A is correct but R is wrong.
(c) A is wrong but R is correct.
(d) Both A and R are wrong.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

V. Find the odd one out.

Question 1.
He, Ne, O2, N2, Pt
Answer:
Pt. It is adsorbent and all others are adsorbates.

Question 2.
SO2, NH3, NaCI, Silica gel
Answer:
Silica gel. It is an adsorbent whereas others are adsorbates.

Question 3.
Silica gel, Pt, Ag, Pd, NH3
Answer:
NH3 It is an adsorbate whereas others are adsorbents.

Question 4.
Coconut charcoal, silica gel, mica, SO2, Animal charcoal
Answer:
SO2 It is an adsorbate whereas others are adsorbents.

Question 5.
Mica, Nickel, Charcoal, Tungsten, Ethyl alcohol vapours
Answer:
Ethyl alcohol vapours. It is an adsorbate whereas others are adsorbents.

Question 6.
Pt, Glycerol, MnO2, Ni, I2
Answer:
Glycerol. It is a negative catalyst whereas others are positive catalyst.

Question 7.
Fe, Anhydrous AlCl3, V2O5, Pt, Ethyl alcohol
Answer:
Ethyl alcohol is a negative catalyst whereas others are positive catalyst.

Question 8.
Decomposion of acetaldehyde by I2 Decomposition of H2O2 by Pt, Ester hydrolysis with acid, Hydrolysis of cane sugar.
Answer:
Decomposition of H2O2 by Pt. It is heterogeneous catalysis whereas others are homogeneous catalysis.

Question 9.
Friedel crafts reactopm, Haner’s process, Hydrolysis of cane sugar, contact process.
Answer:
Hydrolysis of cane sugar. It is homogeneous catalysis whereas others are heterogeneous catalysis.

Question 10.
Pepsin, Zymase, Maltase, Diastase, Maltose, Urease.
Answer:
Maltose. It is a carbohydrate whereas others are enzyme catalysts.

Question 11.
Pt, Ni, Fe°/Pd°, Fe/Mo, Sn/HCI
Answer:
Fe°/Pd°. It is a nano catalyst where as others ordinary catalyst.

Question 12.
Milk, coffee, smoke, common salt solution, dust.
Answer:
Common salt solution. It is a true solution whereas others are colloids.

Question 13.
Soda water, Butter, Starch solution, Cheese, Cream.
Answer:
Starch solution. It is a suspension whereas others are colloids.

Question 14.
Ink, Milk, Cream, Mayonnaise.
Answer:
Ink. It is a sol whereas others are Emulsion.

Question 15.
Pearls, Opals, Coloured glass, Alloys, Pumice stone.
Answer:
Pumice stone. It is a solid foam whereas others are solid sol.

Question 16.
Smoke, Froth, Fumes, Dust, Air pollutants.
Answer:
Froth. It is a foam whereas others are solid aerosol.

Question 17.
Pumice stone, Foam, Milk, Rubber band.
Answer:
Milk. It is an emulsion whereas others are solid foam.

Question 18.
Mechanical dispersion, Bredigts arc method, Peptisation, Double decomposition, Ultrasonic dispersion.
Answer:
Double decomposition. It is a condensation method of preparation of colloids whereas others are dispersion methods of preparation of colloids.

Question 19.
Oxidation, Peptisation, Reduction, Decomposition, Hydrolysis.
Answer:
Peptisation. It is a dispersion method of preparation ofcoiloid whereas others are condensation methods of preparation of colloids.

Question 20.
Dialysis, electrophoresis, Ultrafi iteration. Electrodialysis.
Answer:
Electrophoresis is an electrical property of colloids but others are purification methods of colloids.

Samacheer Kalvi 12th Chemistry Surface Chemistry 2 Marks Questions and Answers

Question 1.
Define

  1. Adsorbent
  2. Adsorbate with an example.

Answer:

  1. Adsorbent is a material on which adsorption takes place. eg., silica gel and metals like Ni, Cu, Pt.
  2. Adsorbate is a substance which is adsorbed on the adsorbent. e.g., Gaseous molecules like He, Ne, O2, N2 and solutions of NaCI (or) KCI.

Question 2.
Define

  1. Interface
  2. Desorption.

Answer:
1. Interface:
The surface of separation of the two phases where the concentration of adsorbed molecule is high is known as interface.

2. Desorption:
The process of removing an adsorbed substance from the substance is called desorption.

Question 3.
What is adsorption? What is meant by positive and negative adsorption?
Answer:
Adsorption is the odhesion of atoms, ions or molecules from a gas, liquid or dissolved solid to a surface. In adsorption, if the concentration of a substance in the interface is high, then it is called positive adsorption. 1f it is less, then it is called negative adsorption.

Question 4.
Define chemical adsorption? Give example.
Answer:
Chemical adsorption is a process in which gas molecules are held to the surface by formation of chemical bonds. e.g., Adsorption of O2 on tungsten, Adsorption of H2 on nickel.

Question 5.
Chemical adsorption is an exothermic process. Justify this statement.
Answer:
In chemical adsorption, gas molecules are held to the surface by the formation of strong bond. Due to this 400kJ/mole is given out as heat of adsorption. Since heat is evolved, it is an exothermic process.

Question 6.
Why physical adsorption take place at low temperature?
Answer:
In physical adsorption, the forces between the adsorbent and adsorbate are very weak, heat of adsorption is low and hence physical adsorption occurs at low temperature.

Question 7.
What are the forces exist in physical adsorption?
Answer:
In physical adsorption, physical forces like van der Waals force of attraction exist between adsorbent and adsorbate.
The other forces that can cause physical adsorption are

  1. dipole-dipole interaction
  2. dispersion forces.

Question 8.
What is physical adsorption? Give example.
Answer:
Physcial adsorption is a process in which adsorbate are attached to adsorbent by means of weak van der Waals forces of attraction. e.g.,

  1. Adsorption of N2 on mica
  2. Adsorption of gases on charcoal.

Question 9.
Finely divided Nickel is a better adsorbent than Nickel crystal.
Answer:
As the adsorption is a surface phenomenon it depends on the surface area of adsorbent. i.e., higher the surface area, higher is the amount adsorbed. Finely divided Nickel has longer surface area and it is a better adsorbent than Nickel crystal.

Question 10.
NH3, CO2 are readily adsorbed where as H2, N2 are slowly adsorbed. Give reason.
Answer:
1. The nature of adsorbate can influence the adsorption. Gases like NH3 CO2 are easily liquefiable as have greater van der Waals forces of attraction and hence readily adsorbed due to high critical temperature.

2. But permanent gases like H2, N2 can not be easily liquefied and having low critical temperature and adsorbed slowly.

Question 11.
What is meant by adsorption isotherm?
Answer:
A plot between the amount of adsorbate adsorbed and pressure or concentration of adsorbate at constant temperature is called adsorption isotherm.

Question 12.
Mention Freundlinch adsorption isothermal equation.
Answer:
Freundlinch adsorption isotherm
\(\frac{x}{m}=k p^{1 / n}\)
where x is the amount of adsorbate or adsorbed on ‘m’ gm of adsorbent at a pressure of p. k and n arc constants.

Question 13.
What are the limitations of Freundlich adsorption isotherm?
Answer:

  1. The Freundlich adsorption isotherm is purely empirical and valid over a limited pressure range.
  2. The values of constants ‘k’ and ‘n’ also found vary with temperature. No theoritical explanations were given.

Question 14.
How is adsorption applied in the decolourisation of sugar?
Answer:
Sugar prepared from molasses is decolourised to remove coloured impurities. Animcal charcoal is applied to adsorb colouring impurities and sugar is purified.

Question 15.
What is chromatography?
Answer:
1. The chromatographic technique is a process of separation of components in a mixture which is mainly based on adsorption of components on the surface of adsorbents.

2. This method is very effective and used for identification, detection and estimation of many substances even if they are contained in micro quantities.

Question 16.
Explain the application of adsorption ¡n qualitative analysis with an example.
Answer:
1. In the identification of Al3+ ion in Al(OH)3 is obtained as blue lake. Due to adsorption of blue litmus solution added to the aluminium ion solution.

2. A red colouration is seen due to the acidic nature of the solution. Ammonium hydroxide is added to it until the bkie colour develops.

3. During this addition, Al(OH)3 precipitate is formed with blue colour due to the adsorption of litmus compound.

Question 17.
Define catalyst. Give example.
Answer:
A catalyst is defined as a substance which alter the rate of chemical reaction without itself undergoing chemical change. The phenomenon which involves the action of a catalyst is called catalysis.
e.g.,Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-35

Question 18.
What is homogeneous catalysis? Give example.
Answer:
Homogeneous catalysis is a process in which the reaction, products and catalyst are present in the same phase. NO
e.g. Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-36
In the above reaction, the catalyst NO, the reactants SO2, O2 and product SO3 are present in the gaseous form

Question 19.
What is heterogeneous catalysis? Give example.
Answer:
Heterogeneous catalysis is a process in which the reactants, products and catalyst are present in different phases.
e.g. Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-37

Question 20.
What are promoters? Explain with example.
Answer:
1. In a catalysed reaction, the presence of a certain substance increases the activity of a catalyst. Such substance is called a promoter.

2. For example, in Haber’s process of manufacture of ammonia, the activity of the iron catalyst is increased by the presence of molybdenum. Hence molybdenum is called a promoter.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-38

Question 21.
What is meant by catalyst poison?
Answer:
1. The substances when added to a catalysed reaction decreases or completely destroys the activity of a catalyst are often known as catalytic poisons.

2. In the reaction 2SO2 + O2 → 2SO3 with Pt catalyst, the catalyst poison is AS2O3.

Question 22.
Which is the catalyst and catalyst poison In Haber’s process?
Answer:
In the Haber’s process of the manufacture of ammonia, the Fe is catalyst and it is poisoned by the presence of H2S.
3H2 + N2 → 2NH3 Fe – catalyst, H2S – Catalyst poison

23. In the reaction 2H2 + O2 → 2H2O, which ¡s the catalyst and catalyst poison?
Answer:

  1. Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-39 Pt – catalyst
  2. CO act as catalytic poison for Pt catalyst.

Question 24.
Explain the relation between activation energy and the rate of the reaction using catalyst.
Answer:
1. For a chemical reaction to occur, the reactants are to be activated to form a activated complex. The energy required for the reactants to reach the activated complex is called the activation energy. The activation energy can be decreased by increasing the reaction temperature.

2. In the presence of catalyst, the reactants are activated at reduced temperatures. i.e., the activation energy is lowered. The catalyst adsorbs the reactants activates them by weakening the bonds and allow them to react to form products.

3. As activation energy is lowered in the presence of a catalyst, more molecules take part in the reaction and hence the rate of the reaction increases.

Question 25.
What are the merits and limitations of the intermediate compound theory?
Answer:
Merits:

  1. The specificity of a catalyst
  2. The mercase in the rate of the reaction with increase in the concentration of catalyst.

Limitations:

  1. This theory fails to explain the action of catalytic poison and promoters.
  2. This theory is unable to explain the mechanism of heterogeneous catalysed reactions.

Question 26.
What are active centres?
Answer:

  1. The surfiice of a catalyst is not smooth. It bears steps, cracks and corners. Hence the atoms on such locations of the surface are coordinatively unsaturated.
  2. The have residual force of attraction. Such sites are called active centres. So the surface cames high surface free energy.

Question 27.
Enzyme catalysis are more effective and efficient than ordinary catalysis. Prove this statement.
Answer:
1. Effective and efficient conversion ¡s the special chareteristic of enzyme catalysed reactions. An enzyme may transform a million molecules of reactant to product in a minute.
For e.g. 2H2O2 → 2H2O + O2

2. For this reaction colloidal platinum as a catalyst the activation energy is 11 .7 k.cal/mole. But with the enzyme catalyst the activation energy of this reaction is less than 2k.cal/mole.

Question 28.
Enzyme catalysis is highly specific in nature. Justify this statement.
Answer:
1. Urea can be hydrolysed to urea by the enzyme urease.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-40
The catalyst mease (enzyme) catalyses urea but it does not hydrolyse methyl urea.

Question 29.
Enzyme catalysed reaction has maximum rate at optimum temperature. Prove it.
Answer:
1. At first rate of reaction increases with the increase of temperature, but above a particular temperature, the activity of enzyme is destroyed. The rate may even drop to zero. The temperature at which enzymic activity in high or maximum is called optimum temperature.

2. For e.g., enzymes involved in human body have an optimum temperature 37°C/98°F.

Question 30.
What are the types of colloids based on dispersion medium?
Answer:

1. If the dispersion medium considered as water, then the colloids are referred as hydrosols (or) aquasols.
2. If the dispersion medium is an alcohol, the colloid is termed as alcosol. and if benzene is the dispersion medium, it is called benzosol.

Question 31.
Explain about

  1. Liquid aerosol
  2. solid aerosol with example.

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-41

Question 32.
Explain oxidation method of preparation of colloids with two examples.
Answer:
Oxidation:
1. When hydrolodic acid is treated with iodic acid 12 sol is obtained.
HIO3 + 5HI → 3H2O + 3I2 (sol)

2. When O2 is passed through H2Se, a sol of selenium is obtained.
H2Se + O2 → 2H2O + Se (sol)

Question 33.
Explain the method of preparation of gold sol by reduction method.
Answer:
Gold sol is prepared by the reduction of auric chloride using formaldehyde.
2AuCl3 + 3HCHO + 3H2O → 2Au (sol) + 6HCI + 3HCOOH

Question 34.
How would you prepare ferric hydroxide sol by hydrolysis method?
Answer:
Fe(OH)3 sol can be preparcd by the hydrolysis of FeCl3
FeCI3 + 3H2O → Fe(OH)3 (soL) + 3 HCI

Question 35.
How would you prepare colloid by the exchange of solvent method?
Answer:
1. Colloidal solution of few substances like phosphorous or sulphur is obtained by the solutions in alcohol and pouring them into water.
2. As they are insoluble in water, they form colloidal solution.
P in alcohol + water → Psol.

Question 36.
Why colloids are to be purified? If not what will happen?
Answer:

  1. The colloidal solutions due to their different methods ofpreparation may contain impurities.
  2. If they are not removed, they may destabilise and precipitate the colloidal solution. This is called coagulation.
  3. Hence the impurities mainly electrolytes should be removed to increase the stabilisation of colloid.

Question 37.
How is human kidney dialysis take place?
Answer:

  1. Kidney malfunction results in the building up of electrolyte concentration within the blood to toxic levels.
  2. In the dialysis. recycling of patient’s blood is done through considerable length of semipermeable tube in an isotomic saline solution.

Question 38.
Write a note about Helmoholtz double laver.
Answer:
The surface of a colloidal particle adsorbs one type of ion due to preferential adsorption. This Stem layer
layer attracts the oppositely charged ions in the. medium and hence the boundary separating the Slpping plane two electrical double layers are set up. This is called Helmholtz electrical double layer. As the particles nearby are having similar charges. they cannot come close and condense. Hence this helps to explain the stability of the colloid.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-42

Question 39.
What is meant by gold number?
Answer:

  1. Zsigmondy introduced the term “Gold number” as a measure of protective power of a colloid.
  2. Gold number is defined as the number of milligrams of hydrophilic colloid that will just prevent the precipitation of 10 ml of gold sol on the addition of 1 ml of 10% NaCI solution.

Question 40.
Potato starch is less stable than gelatin. Why?
Answer:

  1. The gold number of gelatin is 0.005 – 1 and the gold number of potato starch is 25.
  2. Smaller the gold number, greater the protective power.

Question 41.
Write a note about Cortrell’s precipitator.
Answer:
Carbon dust in air is solidified by Cortrell’s precipitator. In it. a high potential difference of about 50.000V is used. The change on carbon is neutralised and solidified. Thus the air is free from carbon particles.

Question 42.
Explain about

  1. blue colour of the sky
  2. formation of delta.

Answer:

  1. The blue colour of the sky in nature is due to Tyndall effect of air particles.
  2. The electrolytes in sea and river water coagulate the solid particles in river water at their intersection. By this way delta is formed.

Question 43.
Distinguish between the meaning of the terms adsorption and absorption. Give one example each.
Answer:
Adsorption

  1. Substance is concentrated only at the surface and does notpcnctrate from the surface to the bulkofthe adsorbent.
  2. It is a surface phenomenon.
    Example: Silical gel absorbs water vapour on its surface.

Absorption

  1. Substnce is uniformly distributed throughout the bulk of the solid.
  2. It is a bulk phenomenon.
    Example: Anhydrous CaCl, absorbs water vapours in it.

Question 44.
Explain the following term giving a suitable example, emulsification.
Answer:
The process of making emulsion using a mixture of two immiscible or partially miscible liquids is called emulsification. For example. Cod liver oil is an emulsion made up of water in oil.

Question 45.
What is the reason for the stability of colloidal sols?
Answer:
Reason for the stability of colloidal sols are:

  1. Coagulation of the colloidal sol is prevented because of the presence of equal and similar charges on the colloidal particles.
  2. Colloidal particles are covered by a sheath of liquid in which they are extensively solvated because of which they acquire stability.

Question 46.
Dialysis is a method of purification of sols. But prolonged dialysis of the sol makes it unstable. Why?
Answer:
Traces of electrolytes in the sol, impart charge to the dispersed phase particles making it stable. Prolonged dialysis removes all the electrolytes, thus making the sol unstable.

Question 47.
Why the sun looks red at the time of setting? Explain on the basis of colloidal properties.
Answer:
At the time of setting, the sun is at the horizon. The light emitted by the sun has to travel a longer distance. As a result the blue part of the light is scattered away by the dust particles in the atmosphere. Hence the red part is visible.

Question 48.
What are emulsions? What are their different types? Give one example of each type.
Answer:
An emulsion is a colloidal dispersion in which both the dispersed phase and the dispersion medium are liquids and the two liquids involved are otherwise immiscible.
1. Oil in water type, in which oil is a dispersed phase and water is the dispersion medium, For example: milk is as emulsion of liquid fat dispersed in water.

2. Water in oil type. in which water is the dispersed phase and oil is thedispersion medium. For example: cod liver oil is an emulsion of water in oil in which water is the dispersed phase and oil is the dispersion medium.

Question 49.
How does chemical adsorption of a gas on a solid vary with temperature?
Answer:
Chemical adsorption first increases with increase in temperature and then it decreases, if the pressure remains constant.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-43

Question 50.
What are lyophilic and lyophobic sols? Give one example of each type. Why are hydrophobic sols easily coagulated?
Answer:
Lyophilic Sols:
Colloidal sols directly formed by rnixing substances like gums, gelatin, starch, rubber. etc. with a suitable liquid (The dispersion medium) are lyophilic sols. An important characteristic of these sols is that if the dispersion medium is separated from the dispersed phase

(say by evaporation) the sol can be reconstituted by simply remixing with the dispersion medium. That is why these sols are also called reversible sols. These sols are quite stable and cannot be easily coagulated.

Lyophobic sols:
These colloidal sols can only be prepared by some special methods. These sols are readily precipitated on the addition of small amount of electrolytes, by heating or by shaking and hence are not stable.

Hydrophobic sols are water hating. They are formed by indirect method. These sols are irreversible sols. These sols are readily precipitated by the addition of small amount of electrolytes, by heating or by shaking and hence are not stable.

Samacheer Kalvi 12th Chemistry Surface Chemistry 3 Marks Questions and Answers

Question 1.
What are the characteristics of adsorption?
Answer:
1. Adsorption can occur in all interfacial faces i.e., the adsorption can occur in between gas – solid, liquid – solid, liquid – liquid, solid – solid and gas – liquid.

2. Adsorption is always accompanied by decrease in free energy. When ∆G reaches zero, the equilibrium is attained.

3. Adsorption is a spontaneous process.

4. When molecules are getting adsorbed, there is always decrease in randomness of the molecules.
∆G = ∆H – T∆S where ∆G = change in free energy
∆H change in enthalpy
∆S change in entropy
∆H = ∆G + T∆S

5. Adsorption is exothermic and it is a quick process.

6. If simultaneous adsorption and absorption take place, it is termed as ‘sorption and sorption of gases on metal surface is called occlusion.

Question 2.
Explain graphical representation of chemical adsorption and physical adsorption.
Answer:
1. Adsorption isotherms represents the variation of adsorption at constant temperature.

2. When amount ?f adsorption is plotted versus temperature at constant pressure is called adsorption iso bar
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-44
3. In physical adsorption x/m decreases with increase in T. But in chemical adsorption x/m increases with rise in temperature and then decreases. The increase illustrate the requirement of activation of the surface for adsorption is due to the fact that formation of activated complex require certain energy. The decrease at high temperature is due to desorption, as the kinetic energy of the adsorbate increases.

Question 3.
Write any 3 applications of adsorption.
Answer:

  1. Gas masks: During World War I. charcoal gas mask was employed.
  2. To create high vaccum in vessels, activated charcoal is used. For dehydration and purification of gases like CO2, N2, O2 and He, alumina and silica gel are employed.
  3. In blast furnace, silica gel is used for drying air.

Question 4.
Explain the function of permutit in the softening of hard water.
Answer:
1. Permutit is employed for softening 6 hard water. It adsorbs Ca2 and Mg2 ions in its surface, there is an ion exchange as shown below it occurs on the surface.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-45

2. Exhausted permutit is generated by adding a solution of commonsalt.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-46

Question 5.
Explain about the application of ion exchange resins In adsorption.
Answer:

  1. Ion exchange resins are working only based on the process of adsorption.
  2. Ion exchange resins are used to demmeralise water. This process is carried out by passing water through two columns of cation and anion exchange resins.

Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-47

Question 6.
What is catalysis? Explain with two examples.
Answer:
Catalysis is a process in which a chemical reaction takes place in a faster rate with the help of catalyst.
Haber’s process:
N2 + 3H2 → 2NH3 In this process. Fe is the catalyst and Mo is the promoter.
The surface of Fe catalyses the reaction.

Vanaspathi preparation:
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-48
Nickel surface catalyses the reaction.

Question 7.
In the following fields, how adsorption ¡s applied?

  1. Medicine
  2. Metallurgy
  3. Mordant & Dyes
  4. indicators

Answer:
1. Medicine:
Drugs cure diseases by adsorption on body tissues.

2. Metallurgy:
Sulphide ores are concentrated by a process called froth floation in which lighter ore particles are adsorbed by pine oil. .

3. Mordants and Dyes:
Most of the dyes are adsorbed on the surface of the fabric. Mordants are the substances used for fixing dyes onto the fabric.

4. In the precipitation titrations, the end point is indicated by an external indicator which changes its colour aller getting absorbed on precipitate. It is used to indicate the end point of filtration.

Question 8.
Differentiate homogeneous and heterogeneous catalysis.
Answer:
Homogeneous catalysis

  1. The reaction in which, the reactants, products and catalyst are present in the same phase, is called homogeneous catalysis.
  2. Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-49
  3. Homogeneous catalysis mechanism is ex plained by intermediate compound formation theory.

Heterogeneous catalysis

  1. The reaction in which the reactants, products and catalyst are present in different phases is called heterogeneous calalysis.
  2. Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-50
  3. Heterogeneous catalysis mechanism is explained by adsorption theory.

Question 9.
Give three examples for homogeneous catalysis.
Answer:
1. Decomposition of acetaldehyde by I2 catalyst.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-51

2. Hydrolysis of cane sugar with mineral acid
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-52

3. Acid hydrolysis of an ester
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-53

Question 10.
Give three examples for heterogeneous catalysis
Answer:
1. hydrogenation of ethylene in the presence of Nickel
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-54

2. Decomposition of H2O2 with Pt catalyst
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-55

3. Friedel crafts reaction
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-56

Question 11.
What is auto ctalysis? Give two examples
Answer:
The process in which one of the product formed act as a catalyst is termed auto catalysis
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-57
Acetic acid acts as auto catalyst.
Decomposition of Arsenic hydride
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-58
Arsenic act as auto catalyst.

Question 12.
What is negative catalysis? Explain with example.
Answer:

1. In certain reactions, presence of certain substances decreases the rate of the reaction. Such substances are called negative catalyst and the process is called negative catalysis.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-59

2. In oxidation of chloroform, ethanol decreases the rate of the reaction and ethanol act as negative catalyst.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-60

Question 13.
Explain the formation of water with copper catalyst by Intermediate compound formation theory.
Answer:
1. Formation of water due o the reaction of H2 and O2 in the presence of Cu can be given as

2. Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-61

3. Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-62

Question 14.
Explain the mechanism of oxidation of HCl by air in the presence of CuCl2
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-63

Question 15.
Explain the thermal decomposition of potssium chlorate by intermediate compound formation theory.
Answer:
1. Thermal decomposition of KClO3 in the presence of MnO2 proceeds as follows.

2. Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-64

Question 16.
Describe the action of active centres present in the catalyst.
Answer:
1. Active centres increases the rate of the reaction by adsorbing and activating the reactants.

2. Increase in the activity of a catalyst by increasing the surface area. Increase in the surface area of metals and metal oxides by reducing the particle size increases the rate of the reaction.

3. The action of catalytic poison occurs when the poison blocks the active centres of the catalyst.

4. A promoter (or) activator increases the number of active centres on the surface.

Question 17.
Write a note about nano catalyst.
Answer:

  1. Nano materials such as metallic nano particles, metal oxide are used as catalyst in many chemical transformation.
  2. Nano catalysts carry the advantages of both homogeneous and heterogeneous catalysis.
  3. Like homogeneous catalyst the nino catalyst give 100% selective transformations and excellent yield and show extremely high reactivity.
  4. Like the heterogeneous catalyst, nano catalysts can be recovered and recycled.
  5. Nano catalysts are actually soluble heterogeneous catalyst.Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-65

Question 18.
Differentiate lyophillic and lyophobic colloids
Answer:
Lyophiltic colloids

  1. In lyophillic colloids (or) sols definite attractive force (or) affinity exists between dispersion medium and dispersed phase.
  2. e.g., Sols of protein, starch
  3. They are more stable and will not get precipitated readily.
  4. They can be brought back to colloidal solution even after the precipitation by addition of dispersion medium
  5. They arc called reversible sols

Lyophobic colloids

  1. In lyophobic colloid no attractive force exists between dispersed phase and dispersed phase and dispersion medium.
  2. e.g., sols of gold, silver
  3. They are less stable and get precipitated readily
  4. They cannot be produced again by adding the dispersion medium.
  5. They are called irreversible sols.

Question 19.
Explain about dispersion mediu, dispersed phase and example of

  1. foam,
  2. emulsion
  3. sol

Answer:

Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-66

Question 20.
Explain about dispersion medium, dispersed phase and example of

  1. solid foam
  2. Gel
  3. Solid sol.

Answer:

Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-67

Question 21.
How would you prepare colloids of ink and graphite? (OR)
Answer:
Explain about mechanical ‘dispersion method.
1. Using a colloid mill, the solid is ground to colloidal dimension. Coarse dispersion The colloid mill consists of two metal plates rotating in opposite directions at very high speed of nearly 7000 revolution per minute.

2. The colloidal particles of required colloidal size is obtained by adjusting the distance between the two plates.

3. By this method, colloidal solutions of ink and graphite and prepared.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-68

Question 22.
Explain about Bredic’s arc method (or) Electro dispersion method (or) How would you prepare colloids of noble metals?
Answer:
1. An electrical arc is struck between electrodes dispersed in water surrounded by ice. When a current of I amp! 100V is passed, an arc produced forms vapours of metal which immediately condense to from colloidal solution.

2. By this method, colloidal solution of many metals like copper, silver, gold. platinum can be prepared.

3. Alkali hydroxide is an added an stabilising agent for the colloid solution.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-69

Question 23.
Explain about ultrasonic dispersion. (or) How would you prepare mercury colloid?
Answer:
1. Sound waves of frequency more than 20kHz (audible limit) could cause transformation of coarse suspension to colloidal solution.

2. Claus obtained mercury sol by subjecting mercury to sufficiently high frequency ultrasonic vibrations.

3. The ultrasonic vibrations produced by generator spread the oil and transfer the vibration to the vessel with mercury in water.

Question 24.
Explain the methods of preparation of colloids of

  1. AS2S3
  2. S.

Answer:
1. Double decomposition:
When hydrogen suiphide gas is passed through a solution of arsenic oxide, a yellow coloured arsenic sulphide is obtained as a colloidal solution.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-70

2. Decomposition:
When few drops of an acid is added to a dilute solution of sodium thio sulphate, the insoluble free sulphur produced by the decomposition of sodium thiosuiphate accumulates into clusters which impart various colours blue, yellow and even red to the system depending on their growth within the size of colloidal dimensions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-71

Question 25.
Describe about

  1. Dialysis
  2. Electro dialysis.

Answer:
1. Dialysis:
Thomas Graham separated the electrolyte from a colloid using a semipermeable membrane. In this method, the colloidal solution is taken in a bag made up of semipermeable membrane. It is suspended in a trough of flowing water, the electrolytes diffuse out of the membrane and they are carried away by water. membrane and they are carried away by water.

2. Electro dialysis:
The presence of electric field increases the speed of removal of electrolytes from colloidal solution. The colloidal solution containing an electrolyte as impurity is placed between two dialysing membranes enclosed into two compartments filled with water.

When current is passed, the impurities pass into water compartment and get removed periodically. This process is faster than dialysis, as the rate of diffusion of electrolytes is increased by The application of electricity.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-72

Question 26.
Explain about ultrafiltration.
Answer:
1. The pores of ordinary filter papers permit the passage of colloidal solutions. In ultrafilteration, the membranes are made by using collodion, cellophane or visiking.

2. Vhen a colloidal solution is filtered using such a filter, colloidal particles are separated on the filter and the impurities are removed as washings.

3. This process is quickened by application of pressure. The separation of sol particles from electrolyte by fikration through an ultrafilter is called ultrafiltration.

4. Collodian is 4% solution of nitrocellulose in a mixmre of alcohol and water.

Question 27.
Write a note about shape of colloidal particles.
Answer:
Colloidal particles possess various shapes.
Collidal particle

  1. AS2S3
  2. Fe(OH)3 (blue gold sol)
  3. W3O5 sol(tungstic acid sol)

Shape

  1. Spherical
  2. Disc (or) plate like
  3. Rod like

Question 28.
What is meant by Tyndall effect? (or) Explain about the optical property of colloid.
Answer:
Answer:

  1. Colloids have optical property. When a homogeneous solution is seen in the direction of light, it appears clear but it appears dark in a perpendicular direction.
  2. When light passes through colloidal solution, it is scattered in all direction and it is known as Tyndall effect.
  3. The colloidal particles absorbs a portion of light and remaining portion is scattered from the surface of the colloid. Hence the path of light is made clear.

Question 29.
What is meant by Brownian movement?
Answer:
1. Robert Brown observed that when the pollen grains suspended in water were viewed through an ultra microscope, they showed a random, zigzag, ceaseless motion. This is called Brownian movement of colloidal particles.

2. The colloidal sol particles are continuously bombard with the molecules of dispersion mediuri and hence they follow a zigzag. random, continuous movement.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-73

Question 30.
Mention the uses of Brow nian movement.
Answer:
1. Brownian movement enables us to calculate Avogadro Number.

2. It is used to confirm kinetic theory which considers the ceaseles rapid movement of molecules that increases with increase in temperature.

3. It is used to understand the stability of colloids. As the particles are in continuous rapid movement, they do not come close and hence not get condensed. That is Brownian movement does not allow the particles to be acted on by force of gravity.

Question 31.
What is coagulation? Mention the method used to coagulate a colloid.
Answer:

  1. The flocculation and setting down of the sol particles is called coagulation.
  2. Various methods of coagulation are
  3. addition of an electrolyte
  4. Electrophoresis
  5. mixing oppositely changed sols
  6. boiling

Question 32.
The precipitation power of ions are in the order Al3+ > Ba2+ > Na+.
Similarly [Fe(CN)6]4-SO42- Cl. Give the reason behind this.
Answer:
1. A negative ion causes the precipitation of positively changed sol and vice versa.

2. When the valency of ion is high, the precipitation power increased. So in cations the precipitation power order is Al3+ > Ba2+ > Na and in anions the precipitation power order is [Fe(CN)6]4- > SO42- > Cl.

3. The precipitation power of electrolyte is determined by finding the minimum concentration required to cause precipitation of sol in 2hrs. This value is called flocculation value. The smaller the flocculation value, greater will be precipitation.

Question 33.
Explain how coagulation of colloid is carried out by

  1. Flectrophoresis
  2. By mixing two oppositely changed sols
  3. By boiling.

Answer:
1. Electrophoresis:
In eleetrophoresis, charged particles migrate to the electrodes of opposite sign. It is due to neutralization of the charge of the colloids. The particles are discharged and sothey get precipitated.

2. By mixing two oppositely charged sols: When colloidal sols with opposite charges are mixed, mutual coagulation takes place. It is due to migration of ions from the surface of the particles.

3. By boiling – When colloidal sol is boiled, due to increased collisions, the sol particles combine and settle down.

Question 34.
Explain about protective action of colloid.
Answer:
1. Lyophobic sols are precipitated readily even with small amount of electrolytes. But they are stabilised by the addition of small amount of lyophillic colloid.

2. A small amount of gelatine sol is added to gold sol to protect gold sol.

3. Gold number is a measure of protecting power of a colloid, Gold number is defined as the number of milligrams of hydrophillic colloid that will just prevent the precipitation of 10ml of gold sol on the addition of imi of 10% NaG solution. Smaller the gold number, greater the protective power.

Question 35.
What are emulsions? Give its types. Explain with examples.
Answer:

  1. Emulsions are colloidal solution in which a liquid is dispersed in another liquid.
  2. There are two types of emulsions.
    • Oil in water (0/W)
    • Water in Oil (W/O)
  3. Oil in Water : Oil dispersed in water. e.g., mayonnaise. icecrearn.
    Water in Oil: Water dispersed in Oil. e.g., stiff grease, butter, cold cream.

Question 36.
Write 3 examples for emulsifiers.
Answer:

  1. Most of the lyophillic colloids act as emulsifiers. Example, glue. gelatin.
  2. Long chain compounds with polar groups like soap and suiphonic acid.
  3. Insoluble powders like clay and lamp black also act as emulsifier,

Question 37.
What is meant by inversion of phase? Explain with example.
Answer:

  1. The change of W/O emulsion into O/W emulsion is called inversion of phase.
  2. Example: An oil in water emulsion containing potassium soap as emulsifying agent can be converted into water in oil emulsion by adding CaCl2 (or) AlCl3. This is called inversion of phase.

Question 38.
Write a note about medicinal applications of colloids.
Answer:

  1. Antibodies such as penicillin and streptomycin are produced in colloidal form for suitable injections. They cure pneumonia.
  2. Colloidal gold and colloidal calcium are used as tonics.
  3. Milk of magnesia is used for stomach troubles.
  4. Silver sol protected by gelatine known as Argyrol is used as eye lotion.

Question 39.
How colloids are used in

  1. Tanning of leather
  2. Rubber industry
  3. Sewage disposal.

Answer:
1. Tanning of leather:
Skin and hides are protein containing positively charged particles which are coagulated by adding tannin to give hardened leather for further application. Chromium salts are used for tanning of leather. Chrome tanning can produce soft and polishable leather.

2. Rubber industry:
Latex is the emulsion of natural rubber with negative particles. By heating rubber with sulphur, vulcanized rubbers are produced for tyres, tubes etc.

3. Sewage disposal:
Sewage containing dirt, mud and wastes dispersed in water. Th e passage of electnic current deposits the wastes materials which can be used as a manure.

Question 40.
How would you distinguish natural honey from artificial honey?
Answer:

  1. Natural honey is a colloidal sol. It is distinguished from artificial one by adding ammonia cal AgNO3.
  2. In the case of natural honey, a metallic silver is produced assumes a reddish yellow colour due to the traces of albumin or ethereal oil which acts as a protective colloid,
  3. In case of artificial honey, a dark yellow (or) greenish yellow precipitate is formed.

Question 41.
Give four uses of emulsions.
Answer:

  1. The cleansing action of soap is due to emulsions.
  2. It is used in the preparation of vanishing cream.
  3. It is used in the preparation of cod liver oiL.
  4. It is used in the preparation of butter, cream etc.

Question 42.

  1. Adsorption of a gas on the surface of solid is generally accompanied by a decrease in entropy. Still ¡t is a spontaneous process. Explain.
  2. How does an increase in temperature affect both physical as well as chemical adsorption?

Answer:
1. According to the equation ∆G = ∆H – T∆S For a process to be spontaneous, ∆G should be negative. ∆H of adsorption is always negative. For a gas. ∆S is also negative. Thus, in an adsorption process, which is spontaneous, a. combination of these two factors always makes ∆G negative.

2. On increasing the temperature desorption occurs in case of physical adsorption. Chemical adsorption first increases and then decreases with increase in temperature.

Question 43.

  1. What is the difference between a colloidal solution and an emulsion? Give one example of each.
  2. What are emulsifiers?

Answer:
1. In a colloidal solution, the dispersed phase is a solid and the dispersion medium is liquid. In an emulsion, both the dispersed phase and the dispersion medium are liquid. Example – Colloidal sol — cell fluids, muddy water. Emulsion – milk, cold cream

2. Emulsifiers – The substance which are added to stabilise the emulsions are called emulsifiers. Example – Soaps of various kinds and lyophilic colloids (proteins, gum etc.)

Question 44.
Explain what is observed when.

  1. KCl, an electrolyte, is added to an hydrated ferric hydroxide sol.
  2. An electric current is passed through a colloidal solution.
  3. A beam of light is passed through a colloidal solution.

Answer:

  1. Feme hydroxide Fe(OH)3 is a positively charged sol, so it gets coagulated by the chloride ions released from KCI solution.
  2. When an electric current is passed through a colloidal solution due to charge on the colloidal particles they migrate towards the oppositely charged electrode.
  3. When a beam of light is passed through a colloidal solution the path of light becomes visible.

Question 45.
Write three distinct differences between physical adsorption and chemisorption.
Answer:
Physical adsorption

  1. Forces of attraction between the adsorbent and adsorbate molecules are weak Van der Waals’ forces,
  2. Heat of adsorption is low (20-40 kJ mol1)
  3. It is temporary and reversible.

Chemical adsorption

  1. Forces between the adsorbent and the adsorbate are strong chemical bond.
  2. Heat of adsorption is high (80-24OkJ mol1)
  3. It is permanent and irreversible.

Question 46.
Explain the following observations.
Answer:

  1. Lyophilic colloid is more stable than lyophobic colloid.
  2. Coagulation takes place when sodium chloride solution added to a colloidal solution of ferric hydroxide.
  3. Sky appears blue in colour.

Answer:
1. A lyophilic sol is stable duc to the charge and the hydration of the sol particles. Such a sol can only be coagulatd by removing the water and adding solvents like alcohol, acetone, etc. and then an electrolyte. On the other hand, a lyophobic soils stable due to charge only and hence it can he easily coagulated by adding small amount of an electrolyte.

2. The colloidal particles get precipitated. i.e., ferric hydroxide is precipitated.

3. The atmospheric particles of colloidal range scatter blue component of the white sunlight preferentially. That is why the sky appears blue.

Question 47.

  1. Heat of adsorption is greater for chemisorption than physisorption. Why?
  2. What is colloldion?
  3. Differentiate between peptization and coagulation.

Answer:

  1. Due to the formation of chemical bond between adsorbate and adsorbent.
  2. 4% solution of nitro cellulose in a mixture of alcohol and ether.
  3. Peptisation is the process of converting a precipitate into colloidal sol by adding an electrolyte. Rut coagulation is the settling of colloidal particles.

Question 48.
Give reasons for the following.

  1. Enzyme catalysts are highly specific in their action.
  2. The path of light beconies visible wheti it is passed through As2S3 sol ¡n water.
  3. The enthalpy in case of chemisorption is usually higher than that of physisorption.

Answer:

1. This is because each enzyme has a specific active site on which only a particular substrate can bind. ,

2. This is because of Tyndall effect caused due to the scattering of light by colloidal particles of As2S3 sol.

3. Chemisorption involves the formation ofa chemical bond between adsorbent and adsorbate molecule which involves high energy changes while in physisorption, the molecules of adsorbate and adsorbent arc held by weak van der Waals’ interactions.

Question 49.
What is adsorption? How does adsorption ola gas on a solid surface vary with pressure? Illustrate with the help of an appropriate graph.
Answer:
Adsorption is the phenomenon of attracting and retaining the molecules of a substance on the surface of a liquid or a solid, resulting in higher concentration of the molecules on the surface.

Effect of pressure:
At constant temperature, the adsorption of gas increases with increase of pressure of the gas. At low pressure. it increases rapidly. At an equilibrium pressure. the extent of adsorption (x/m) reaches its maximum value after which adsorption is independent of pressure.
\(\frac{\mathrm{x}}{\mathrm{m}}=\mathrm{kP}^{1 / \mathrm{n}}\)
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-74

Question 50.
How do size of particles of adsorbent, pressure of a gas and prevailing temperature influence of extent of adsorption of a gas on a solid?
Answer:
1. Effect of size of the particles of adsorbent: Greater the specific area of the solid available for adsorption of adsorbent, greater would be its adsorbing power. That is why porous or finely divided forms of adsorbents more strongly. However, the size of pores should be large enough to allow the diffusion of gas molecules.

2. Effect of pressure:
Increase in pressure initially increases the adsorption which later attains equilibrium at high pressure.
\(\frac{\mathrm{x}}{\mathrm{m}}=\mathrm{kP}^{1 / \mathrm{n}}\) (n>1)

Samacheer Kalvi 12th Chemistry Surface Chemistry 5 Mark Questions and Answers

Question 1.
What is adsorption isotherm? Explain about Freundlich adsorption isotherm.
Answer:
1. Adsorption isotherms represents the variation of adsorption at constant temperature. Adsorption isoterm can be studied quantitatively.

2. A plot between the amount of adsorbate adsorbed and pressure or concentration of adsorbate at constant temperature is called adsorption isotherms.

3. Freundlich adsorption isotherm. According to Freundlich
\(\frac{\mathrm{x}}{\mathrm{m}}=\mathrm{kP}^{1 / \mathrm{n}}\)
Where x is the amount of adsorbate (or) adsorbed on ‘m’ gm of adsorbent at a pressure of P. k and n are constants. Value of’n’ is always less than unity.

4. This equation is applicable for adsorption of gases on solid surfaces. The Same equation becomes \(\frac{\mathrm{x}}{\mathrm{m}}=\mathrm{kc}^{1 / \mathrm{n}}\) when used for adsorption in solutions with ‘c’ as concentration.

5. These equation quantitatively predict the effect of pressure (or concentration) on the adsorption of gases (or adsorbates) at constant temperature.

6. Taking log on both sides of equation
\(\frac{\mathrm{x}}{\mathrm{m}}=\mathrm{kP}^{1 / \mathrm{n}}\)
log \(\frac { x }{ m }\) = log k + \(\frac { 1 }{ n }\) log P
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-75

7. Hence the intercept represents the value of log k and the slope \(\frac { b }{ q }\) gives \(\frac { 1 }{ n }\)

8. This equation explains the increase of with increase in pressure. But experimental values shows the deviation at low pressure.

9. Limitations:

  1. This equation is purely empirical and valid over a limited pressure range.
  2. The value of k and n also found vary with temperatures. No theoretical explanations were given.

Question 2.
Define catalyst. What are the characteristics of catalysts?
Answer:
A catalyst is defined as a substance which alters the rate of chemical reaction without itself undergoing chemical change.
Characteristics of catalyst:
1. For chemical reaction, catalyst is needed in very small quantity. Generally, a pinch of catalyst is enough for a reaction in bulk.

2. There may be some physical changes, but the catalyst remains unchanged in mass and chemical composition in a chemical reaction.

3. A catalyst itself cannot initiate a reaction. It means it cannot start a reaction which is not taking place. Rut, lithe reaction is taking place in a slow rate it can increase its rate.

4. A solid catalyst will be more effective if it is taken in a finely divided form.

5. A catalyst can catalyse a particular type of reaction, hence they are said to be specific in nature.

6. In an equilibrium reaction, presence of catalyst reduces the time for attainment of equilibrium and hence it does not affect the position
of equilibrium and the value of equilibrium constant.

7. A catalyst is highly effective at a particular temperature called as optimum temperature.

8. Presence of a catalyst generally does not change the nature of products.

9. For example 2SO2 + O2 → 2SO3
This reaction is slow in the absence of a catalyst, but fast in the presence of Pt catalyst.

Question 3.
What is enzyme catalysis? Give the characteristics of enzyme catalysed reaction?
Answer:
Enzymes are complex protein molecules with three dimensional structures. They catalyse the chemical reaction in living organism. They are often present in colloidal state and extremely specific in catalytic action. This process is called enzyme catalysis.
Special characteristics of enzyme catalysis:
1. Effective and efficient conversion is the special characteristic of enzyme catalysed reactions. An enzyme may transform a million molecules of reactant in a minute.
For e.g., 2H2O2 → 2H2O + O2
For this reaction, activation energy is 1 8k.cal/mole without a catalyst. With colloidal platinum as a catalyst, the activation energy is 11.7 k.cal/mole. But with the enzyme catalyst. the activation energy of this reaction is less than 2 k.cal / mole.

2. Enzyme catalysis is highly specific in nature.
H2N – CO – NH2 + H2O → 2NH3 + H2O
The enzyme urcase which catalyses the reaction of urea does not catalyse the hydrolysis of methyl urea (NH2 – CO – NHCH3)

3. Enzyme catalysed reaction has maximum rate at optimum temperature. At first rate of the reaction increases with increase of temperature, but above a particular temperature, the activity of enzyme is destroyed. The rate may even drop to zero. The temperature at which enzyrnic activity is high (or) maximum is called as optimum temperature. e.g., enzyme involved in human body have an optimum temperature 37°C / 98°F.

4. The rate of enzyme catalysed reactions varies with the pH of the system. The rate is maximum at a pH called optimum pH.

5. Enzymes can be inhibited i.e., poisoned. Activity of an enzyme is decreased and destroyed by a poison. The physiological action of drugs is related to their inhibiting action. e.g.. sulpha drugs, penicillin inhibits the action of bacteria and used for curing diseases like
pneumonia, dysentery, cholera.

6. Catalytic activity of enzymes is increased by coenzymes or activators. A small non protein (vitamin) called a coenzyme promotes the catalytic activity of enzyme.

Question 4.
Explain about phase transfer catalysis.
Answer:
1. Consider the reactant of a reaction is present in one solvent and the other reactant is present in an another solvent. The reaction between them is very slow, if the solvents are immisible.

2. As the solvents form separate phases, the reactants have to migrate across the boundary to react. But migration of reactants across the boundary is not easy. For such situation, a third solvent is added which is miscible with both. So, the phase boundary is eliminated the reactants freely mix and react fast.

3. But for large scale preparation of any product, use of a third solvent is not convenient as it may be expensive. For such problems, phase transfer catalysis provides a simple solution, which avoids the use of solvents.

4. it directs the use of a phase transfer catalyst (a phase transfer reagent) to facilitate transport of a reactant in one solvent to other solvent where the second reactant is present. As the reactants are now brought together, they rapidly react and form the product.

5. Example – Substitution of C1 and CN in the following reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-76
R Cl = 1 – chloro octane
R CN = 1 – cyano octane

6. By direct heating of two phase mixture of organic 1 – chioro Octane with aqueous sodium cyanide for several days, 1 – cyano octane is not obtained. However, if a small amount of quarternary ammonium salt like tetra alkyl ammonium cation which has hydrophobic and hydrophilic ends, transports CN – from the aqueous phase to the organic phase using its hydrophilic end and facilitates the reactions with 1 – chloro octane as shown below
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-77

7. So phase transfer catalyst, speeds up the reaction by transporting one reactant from one phase to another.

Question 5.
Explain about the classification of colloids based on the physical state of dispersed phase and dispersion medium with example.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-78

Question 6.
Describe about condensation methods of preparation of colloids. (OR) Describe chemical methods of preparation of colloids. When the substance for colloidal particle is present as smalL sized particle, molecule or ion, they are brought to the colloidal dimension by condensation methods.

Answer:
1. Oxidation method:
When hydroiodic acid is treated with iodle acid J, sol is obtained.
HIO3 + 5HI → 3H2O + 3I2(sol)

2. Reduction method:
Gold sol is prepared by reduction of aune chloride using formaldehyde.
2 AuCl3 + 3HCHO + 3H2O → 2 Au(sol) + 6HCI + 3HCOOH

3. Hydrolysis:
Ferric chloride is hydrolysed to get ferric hydroxide colloid
FeCl3 + 3H2O → Fe(OH)3(sol) + 3HCI

4. Double decomposition:
When hydrogen suiphide gas is passed through a solution of arsenic oxide, a yellow coloured arsenic sulphide is obtained as a colloidal solution.
As2O3 – 3H2S → As2S3 + 3H2O

5. Decomposition:
When few drops of an acid is added to a dilute solution of sodium thiosulphate, sulphur colloid is produced by the decomposition of sodium thio sulphate.
S2O32- + 2H+ → S(sol) + H2O + SO2

7. Describe about the properties of colloids.
Answer:
1. Colour:
The colour of a sol is not always the same as the colour of the substance in the bulk. For example, bluish tinge is given by diluted milk in reflected light and reddish tinge in transmitted light.

2. Size:
The size of colloidal particles ranges from Imp to 1pm diameter.

3. Colloidal solutions are heterogeneous in nature:
They have two distinct phases. Experiments like dialysis. ultrafiltration show the heterogeneous in nature but they are considered as borderline cases.

4. Filterability:
As the size of pores in ordinary filter paper are large, the colloidal particles easily pass through the ordinary filter papers.

5. Non setting nature:
Colloidal solutions are quite stable i.e., they are not affected by gravtiy.

6. Concentration and density:
When the colloidal solution is dilute, it is stable. When the volume of medium is decreased, coagulation occurs. Density of sol decreases with
decrease in the concentration.

7. Diffusability:
Unlike true solution, colloids diffuse less readily through membranes.

8. Colligative properties:
The colloidal solutions show colligative properties such as elevation of boiling point, depression in freezing point and osmotic pressure. These. properties are used to determine molecular weight of colloidal particles.

9. Shape of colloidal particles:
Colloidal particles have various shapes

Collidal particle

  1. AS2S3
  2. Fe(OH)3 (blue gold sol)
  3. W3O5 sol(tungstic acid sol)

Shape

  1. Spherical
  2. Disc (or) plate like
  3. Rod like

10. Optical property:
The path of the light is visible when it is passes through a colloidal solution due to the scattering of light by colloidal particles. This is known as Tyndall effect.

11. Kinetic property:
When colloidal solution is viewed through an ultra microscope, they showed a random, zigzag ceaseless motion which is called Brownian movement.

12. Electrical property:
Helmholtz double layer. electrophoresis and electro osmosis are electrical properties of colloids.

Question 8.
Explain about Electrophoresis (or) Cataphoresis (or) How would you detect the presence of charges on sol particles? (or) Explain about the method used to detect the presence of charge on sol particles. Electrophoresis (or) cataphoresis:

Answer:
1. When electric potential is applied across two platinum electrodes dipped in a hydrophilic sol, the dispersed particles move toward one or other electrode. This migration of sol particles under the influence of electric field is called electrophoresis.

2. If the sol particles migrate to the cathode, then they possess positive charges and if the sol particles migrate to the anode, they have negative charges. Thus from the direction Afiet of migration of sol particles, we can determine the charge of the sol particles. Hence electrophoresis is used for the detection of presence of change on the sol particles.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-79

3.
Positively charged coiloids

Fe(OH)3, Al(OH)3
Basic dyes, Haemoglobin

Negatively charged colloids

Ag, Au & Pt, AS2S3,
Clay, Starch

Question 9.
What are emulsion? Mention its type with example. What is emulsification? How the types of emulsions are identified?
Answer:
1. Emulsions arc colloidal solution in which a liquid dispersed in another liquid.

2. Two types of emulsions

  • Oil in Water (O/W) e.g., mayonnaise
  • Water in Oil (W/O) e.g., Butter

3. The process of preparation of emulsion by the dispersal of one liquid in another liquid is called emulsification.

4. Identification of types of emulsions. The two types of emulsions can be identified by the following tests

  • Dye test – A small amount of dye soluble in oil is added to emulsion. The emulsion is shaken well. The aqueous emulsion will not take the colour whereas oily emulsion will take up the colour of the dye.
  • Viscosity test – Viscosity of the emulsion is determined by experiments. Oily emulsions will have higher value than aqueous emulsions.
  • Conductivity test – Conductivity of aqueous solutions are always higher than oily emulsions.
  • Spreading test – Oily emulsions spread readily than aqueous emulsion when spread on an oily surface.

Question 10.
What is deeniulsification? Explain about the various techniques of deemulsification.
Answer:
Emulsion can be separated into two separate layers. This process is called Deemulsification. Various deemulsilication techniques are given below.

  1. Distilling of one component
  2. Adding an electrolyte to destroy the charge.
  3. Destroying the emulsifier using chemical methods.
  4. Using solvent extraction to remove one component.
  5. By freezing one of the components.
  6. By applying centrifugal force.
  7. Adding dehydrating agents for water in oil type.
  8. Using ultrasonic waves.
  9. Heating at high pressures.

Question 11.

(a) How can a colloidal solution and a true solution of the same colour be distinguished from each other?
(b) List four applications of adsorption.

Answer:

  1. The path of light becomes visible when passed through a colloidal solution while it is not visible in case of a true solution. This is because of Tyndall effect caused by the scattering of light by colloidal particles.
  2. Applications of adsorption:
    • Activated charcoal is used in gas masks to remove poisonous gases such as CH4, CO, etc.
    • Animal charcoal is used as decoloriser in the manufacture of sugar.
    • Silica is used for removing moisture.
    • The ion exchange resins are used for removing hardness of water.

Question 12.
Illustrate with examples.

  1. Lyophilic and Lyophobic sols
  2. Homogeneous and Heterogeneous catalysis.

Answer:
1. The substances such as proteins, starch, rubber, etc. directly passes into the colloidal state when brought in contact with the solvent. Such colloids are known as lyophillic sols, The substances like metals, their suiphides. hydroxides, etc. do not form colloidal sol readily when mixed with dispersion medium. The colloidal sols can only be prepared by some special methods. Such sols are called lyophobic sols.

2. Homogeneous catalysis:
Here the reactants and catalyst are present in the same phase. For example, lead chamber process for the manufacture of H2SO4.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-80

Heterogeneous catalysis:
Here the reactants and catalyst are present in different phases. For example, contact process for manufacture of H2SO4.
Samacheer Kalvi 12th Chemistry Solutions Chapter 10 Surface Chemistry-81
Common Errors

  1. Students may get confused with the words absorption and adsorption
  2. There may be a confusion between physical adsorption and chemical adsorption
  3. Catalyst poison and negative catalyst are different.
  4. Colloids : There may be a doubt between dispersed phase and dispersion medium.
  5. Electro dialysis, Electrophoresis, Electro osmosis may get confused.

Rectifications

1. In surface chemistry, we should use only adsorption. Adsorption mainly explains surface phenomenon.
Physical adsorption – Weak Vander walls forces, multilayer formation, Heterogenous catalysis.

2. Chemical adsorption:
Bond formation, mono-layer formation, Homogeneous catalysis.
Catalyst poison: decreases the catalytic activity of catalyst. Negative catalyst: reduces the rate of a chemical reaction.

3. Dispersion medium:
Larger in amount. Dispersed phase – Smaller in amount. Colloid is dispersed phase in dispersion

4. medium. For e.g., smoke is colloid in which carbon solid particles dispersed in air dispersion medium.
Electrodialysis – Purification of colloid by electric current.

5. Electrophoresis:
Movement of colloidal particles (dispersed phase) towards the oppositely charged electrode under the influence of electric current. Electro osmosis: Movement of dispersion medium towards the oppositely charged electrode under the influence of electric current.

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Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry

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Tamilnadu Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry

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Samacheer Kalvi 12th Chemistry Chapter 9 Electro Chemistry Textual Evaluation Solved

Samacheer Kalvi 12th Chemistry Electro Chemistry Multiple Choice Questions
Question 1.
The number of electrons that have a total charge of 9650 coulombs is ………..
(a) 6.22 x 1023
(b) 6.022 x 1024
(c) 6.022 x 1022
(d) 6.022 x 10-34
Answer:
(c) 6.022 x 1022
Hint: IF = 96500 C = 1 mole of e = 6.023 x 1023 e
9650 C = \(\frac{6.22 \times 10^{23}}{96500} \times 9650\) = 6.022 x 1022

Question 2.
Consider the following half cell reactions:
Mn2+ + 2e → Mn E° = – 1.18V
Mn2+ → Mn3+ + e E = – 1.51V
The E for the reaction 3Mn2+ → Mn+2Mn3+, and the possibility of the forward reaction are respectively.
(a) 2.69V and spontaneous
(b) – 2.69 and non spontaneous
(c) 0.33V and Spontaneous
(d) 4.18V and non spontaneous
Answer:
(b) – 2.69 and non spontaneous
Hint: Mn+ + 2e → Mn(E0red) = 1.18V
2[Mn2+ → Mn3+ + e] (E0ox) = – 1.51V
3Mn2++ → Mn3+ + 2Mn3+ + (E0cell) = ?
E0red = (E0ox) + (E0cell)
= – 1.51 – 1.18 and non spontaneous
= – 2.69 V
Since E° is – ve ∆G is +ve and the given forward cell reaction is non – spontaneous.

Question 3.
The button cell used in watches function as follows
Zn(s) + Ag2O(s) + H2O(1) \(\rightleftharpoons\) 2Ag(s) + Zn2+(aq) + 2OH(aq) the half cell potentials are
Ag2O(s) + H2O(1) + 2e →2Ag(S) + 2OH(aq) E° = 034V. The cell potential will be
(a) 0.84V
(b) 1.34V
(c) 1.10V
(d) 0.42V
Answer:
(c) 1.10V
Hint: Anodic oxidation: (Reverse the given reaction)
(E0ox ) = 0.76V cathodic reduction
E0cell = (E0ox) + (E0red) = 0.76 + 0.34 = 1.1V

Question 4.
The molar conductivity of a 0.5 mol dm-3 solution of AgNO3 with electrolytic conductivity of 5.76 x 10-3S cm-1at 298 K is ………….
(a) 2.88 S cm2 mo1-1
(b) 11.52 S cm2 mol-1
(c) 0.086 S cm2 mol-1
(d) 28.8 S cm2 mol-1
Answer:
(b) 11.52 S cm2 mol-1
Hint:
A = \(\frac { k }{ M }\) x 10-3 mol-1 m3
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-2
= 11.52 S cm2 mol-1

Question 5.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-3
Calculate A0HOAC using appropriate molar conductances of the electrolytes listed above at infinite dilution in water at 25°C.
(a) 517.2
(b) 552.7
(c) 390.7
(d) 217.5
Answer:
(c) 390.7
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-4
(426.2 + 91) – (126.5) = 390.7

Question 6.
Faradays constant is defined as
(a) charge carried by I electron
(b) charge carried by one mole of electrons
(c) charge required to deposit one mole of substance
(d) charge carried by 6.22 X 1010 electrons
Answer:
(b) charge carried by one mole of electrons
Hint:
IF = 96500 C = 1 charge of mole of e = charge of 6.022 x 1023 e

Question 7.
How many faradays of electricity are required for the following reaction to occur
MnO4 → Mn2+
(a) 5F
(b) 3F
(C) IF
(d) 7F
Answer:
(a) 5F
Hint:
7MnO4 + 5e → Mn2+ + 4H2O
5 moles of electrons i.e., 5F charge is required.

Question 8.
A current strength of 3.86 A was passed through molten Calcium oxide for 41 minutes and 40 seconds. The mass of Calcium in grams deposited at the cathode is (atomic mass of Ca is 40g / mol and IF = 96500C).
(a) 4
(b) 2
(c) 8
(d) 6
Answer:
(b) 2
Hint: m = ZIt
41mm 40sec = 2500 seconds
= \(\frac { 40 x 3.86 x 2500 }{ 2 x 96500 }\)
Z = \(\frac { m }{ n x 96500 }\) = \(\frac { 40 }{ 2 x 96500 }\)
= 2g

Question 9.
During electrolysis of molten sodium chloride, the time required to produce 0.1 mol of chlorine gas using a current of 3A is ………..
(a) 55 minutes
(b) 107.2 minutes
(c) 220 minutes
(d) 330 minutes
Answer:
(b) 107.2 minutes
Hint: \(\frac { m }{ ZI }\) (mass of 1 mole of Cl2 gas = 71)
t = \(\frac { m }{ ZI }\) mass of 0.1 mole of Cl2 gas = 7.1 g mol-1)
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-6

Question 10.
The number of electrons delivered at the cathode during electrolysis by a current of 1 A in 60 seconds is (charge of electron = 1.6 x 10-19C)
(a) 6.22 x 1023
(b) 6.022 x 1020
(c) 3.75 x 1020
(d) 7.48 x 1023
Answer:
(c) 3.75 x 1020
Hint: Q = It
= 1A x 60S
96500 C charge 6.022 x 1023 electrons
60 C charge = \(\frac{6.022 \times 10^{23}}{96500} \times 960\)
= 3.744 x 1020 electrons

Question 11.
Which of the following electrolytic solution has the least specific conductance?
(a) 2N
(b) 0.002N
(c) 0.02N
(d) 0.2N
Answer:
(b) 0.002N
Hint: In general, specific conductance of an electrolyte decreases with dilution. SO, 0.002N solution has least specific conductance.

Question 12.
While charging lead storage battery
(a) PbSO4 on cathode is reduced to Pb
(b) PbSO4 on anode is oxidised to PbO4
(c) PbSO4 on anode is reduced to Pb
(d) PbSO4 on cathode is oxidised to Pb
Answer:
(c) PbSO4 on anode is reduced to Pb.
Hint: Charging: anode: PbSO4(s) + 2e → Pb (s) + SO4-2 (aq)
Cathode: PbSO4(s) + 2H2O (1) → PbO2 (s) + SO4-2 (aq) + 2e

Question 13.
Among the following cells
I. Leclanche cell
II. Nickel – Cadmium cell
III. Lead storage battery
IV. Mercury cell
Primary cells are …………
(a) I and IV
(b) I and III
(c) III and IV
(d) II and III
Answer:
(a) I and IV

Question 14.
Zinc can be coated on iron to produce galvanized iron but the reverse is not possible. It is because
(a) Zinc is lighter than iron
(b) Zinc has lower melting point than iron
(c) Zinc has lower negative electrode potential than iron
(d) Zinc has higher negative electrode potential than iron
Answer:
(d) Zinc has higher negative electrode potential than iron
Hint: E0Zn+|Zn = – 0.76V and E0Fe2+|Fe = 0.44V. Zinc has higher negative electrode potential than iron, iron cannot be coated on zinc.

Question 15.
Assertion: pure iron when heated in dry air is converted with a layer Of rust.
Reason: Rust has the composition Fe3O4
(a) If both assertion and reason are true and reason is the correct explanation of assertion.
(b) If both assertion and reason are true but reason is not the correct explanation of assertion.
(c) assertion is true but reason is false
(d) both assertion and reason are false.
Answer:
(d) both assertion and reason are false.
Hint: Both are false

  1. Dry air has no reaction with iron
  2. Rust has the composition Fe2O3 x H2O

Question 16.
In H2 – O2 fuel cell the reaction occur at cathode is ……….
(a) O2(g) + 2H2O (l) + 4e → 4OH(aq)
(b) H+(aq) + OH(aq) → H2O (l)
(c) 2H2(g) + O2(g) → 2H2O (g)
(d) H+ + e → 1/2 H2
Answer:
(a) O2(g) + 2H2O (l) + 4e → 4OH(aq)

Question 17.
The equivalent conductance of M/36 solution of a weak monobasic acid is 6mho cm2 and at infinite dilution is 400 mho cm2. The dissociation constant of this acid is ………….
(a) 1.25 x 10-16
(b) 6.25 x 10 -6
(c) 1.25 x 10-4
(d) 6.25 x 10-5
Answer:
(b) 6.25 x 10 -6
Hint: α = \(\frac { 6 }{ 400 }\)
Ka = α2C = \(\frac { 6 }{ 400 }\) x \(\frac { 6 }{ 400 }\) x \(\frac { 1 }{ 36 }\)
= 6.25 x 10-6

Question 18.
A conductivity cell has been calibrated with a 0.01M, 1:1 electrolytic solution (specific conductance (K = 1.25 x 10-3 S cm-1 ) in the cell and the measured resistance was 800Ω at 250 C . The cell constant is,
(a) 10-1 cm-1
(b) 10-1 cm-1
(c) 1 cm-1
(d) 5.7 x 10-12
Answer:
(c) 1 cm-1
Hint: R = p.\(\frac { 1 }{ A }\)
Cell constant = \(\frac { R }{ ρ }\) = k.R \((\frac { 1 }{ ρ } =k)\) = 1.25 x 10-3 f-1cm-1 x 800Ω = 1cm-1

Question 19.
Conductivity of a saturated solution of a sparingly soluble salt AB (1:1 electrolyte) at 298K is 1.85 x 10-5 S m-1. Solubility product of the saltAB at 298K (Λ0m)AB = 14 x 10-3 S m2 mol-1.
(a) 5.7 x 10-2
(b) 1.32 x 1012
(c) 7.5 x 10-12
(d) 1.74 x 10-12
Answer:
(d) 1.74 x 10-12

Question 20.
In the electrochemical cell: Zn|ZnSO4 (0.01M)||CuSO4 (1.0M)|Cu , the emf of this Daniel cell is E1. When the concentration of ZnSO4 is changed to 1.0 M and that CuSO4 changed to 0.0 1M, the emf changes to E2. From the followings, which one is the relationship between E1 and E2?
(a) E1 < E2
(b) E1 > E2
(c) E2 = 0↑E1
(d) E1 = E2
Answer:
(b) E1 > E2
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-7

Question 21.
Consider the change in oxidation state of Bromine corresponding to different emf values as shown in the diagram below:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-8
Then the species undergoing disproportional is …………..
(a) Br2
(b) BrO4
(c) BrO3
(d) HBrO
Answer:
(d) HBrO
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-9
(Ecell)A = – 1.82 + 1.5 = – 0.32V
(Ecell)B = – 1.5 + 1.595 = + 0.095V
(Ecell)C = 1.595 + 1.0652 = – 0.529V
The species undergoing disproportionation is HBrO

Question 22.
For the cell reaction
2Fe3+(aq) + 2I(aq) → 2Fe2+ (aq) + I2(aq)
EC0cell = 0.24V at 298K. The standard Gibbs energy (∆, G0 ) of the cell reactions is …………
(a) – 46.32 KJ mol-1
(b) – 23.16 KJ mol-1
(c) 46.32 KJ mol-1
(d) 23.16 KJ mor-1
Answer:
(a) – 46.32 KJ mol-1

Question 23.
A certain current liberated 0.504gm of hydrogen in 2 hours. How many grams of copper can be liberated by the same current flowing for the same time in a copper sulphate solution?
(a) 31.75
(b) 15.8
(c) 7.5
(d) 63.5
Answer:
(b) 15.8

Question 24.
A gas X at 1 atm is bubble through a solution containing a mixture of 1MY and 1MZ-1 at 25°C . If the reduction potential of Z > Y> X, then
(a) Y will oxidize X and not Z
(b) Y will oxidize Z and not X
(c) Y will oxidize both X and Z
(d) Y will reduce both X and Z
Answer:
(a) Y will oxidize X and not Z

Question 25.
Cell equation: A2+ + 2B → A2+ + 2B
A2+ + 2e → AE° = + 0.34V and log10 K = 15.6 at 300K for cell reactions find E° for
B1 + e → B
(a) 0.80
(b) 1.26
(c) – 0.54
(d) – 10.94
Answer:
(a) 0.80

Samacheer Kalvi 12th Chemistry Electro Chemistry Short Answer

Question 1.
Define anode and cathode
Answer:

  1. Anode: The electrode at which the oxidation occur is called anode.
  2. Cathode: The electrode at which the reduction occur is called cathode.

Question 2.
Why does conductivity of a solution decrease on dilution of the solution?
Answer:
Conductivity always decreases with decrease in concentration (on dilution of the solution) both for weak as much as for strong electrolytes. ¡t is because the number of ions per unit volume that carry the current is a solution decreases on dilution.

Question 3.
State Kohlrausch Law. How is it useful to determine the molar conductivity of weak electrolyte at infinite dilution.
Answer:
Kohlrausch’s law:
It is defined as, at infinite dilution the limiting molar conductivity of an electrolyte is equal to the sum of the limiting molar conductivities of its constituent ions.

Determination of the molar conductivity of weak electrolyte at infinite dilution.
It is impossible to determine the molar conductance at infinite dilution for weak electrolytes experimentally. However, the same can be calculated using Kohlraushs Law. For example, the molar conductance of CH3COOH, can be calculated using the experimentally determined molar conductivities of strong electrolytes HCI, NaCI and CH3COONa.
Λ°CH3COONa = λ°Na+ + λ°CH3COONa …….(1)
Λ°HCl = λ°H+ + λ°Cl ………………(2)
Λ°NaCl = λ°Na+ + λ°Cl …………….(3)
Equation (1) + Equation (2) – Equation (3) gives,
(Λ°CH3COONa) + (Λ°HCl) – (Λ°NaCl) = λ°H+ + λ°CH3COONa = Λ°CH3COONa

Question 4.
Describe the electrolysis of molten NaCI using inert electrodes.
Answer:
1. The electrolytic cell consists of two iron electrodes dipped in molten sodium chloride and they are connected to an external DC power supply via a key.

2. The electrode which is attached to the negative end of the power supply is called the cathode and the one is which attached to the positive end is called the anode.

3. Once the key is closed, the external DC power supply drives the electrons to the cathode and at the same time
pull the electrons from the anode.

Cell reactions:
Na+ ions are attracted towards cathode, where they combines with the electrons and reduced to liquid sodium.
Cathode (reduction)
Na+(I) + eNa(1)
E0 = – 2.7 1V
Similarly, Cl ions are attracted towards anode where they losses their electrons and oxidised to chlorine gas. Anode (oxidation)
2Cl(1) Cl2(g) + 2e
E° = – 1 .36V
The overall reaction is,
2Na+(l) + 2Cl(l) → 2Na(l) + Cl2(g) (g)
E0 = 4.07 V
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-10
The negative E° value shows that the above reaction is a non spontaneous one. Hence, we have to supply a voltage greater than 4.07V to cause the electrolysis of molten NaCI. In electrolytic cell, oxidation occurs at the anode and reduction occur at the cathode as in a galvanic cell, but the sign of the electrodes is the reverse i.e., in the electrolytic cell cathode is -ve and anode is +ve.

Question 5.
State Faraday’s Laws of electrolysis.
Answer:
Faraday’s laws of electrolysis:
1. First law:
The mass of the substance (M) liberated at an electrode during electrolysis is directly proportional to the quantity of charge (Q) passed through the cell. M α Q

2. Second law:
When the same quantity of charge is passed through the solutions of different electrolytes, the amount of substances liberated at the respective electrodes are directly proportional to their electrochemical equivalents. M α Z

Question 6.
Describe the construction of Daniel cell. Write the cell reaction.
Answer:
The separation of half reaction is the basis for the construction of Daniel cell. It consists of two half cells.

Oxidation half cell:
The metallic zinc strip that dips into an aqueous solution of zinc sulphate taken in a beaker.

Reduction half cell:
A copper strip that dips into an aqueous solution of copper sulphate taken in a beaker.

Joining the half cell:
The zinc and copper strips are externally connected using a wire through a switch (k) and a load (example: volt meter). The electrolytic solution present in the cathodic and anodic compartment are connected using an inverted U tube containing a agar-agar gel mixed with an inert electrolyte such as Kl1, Na2SO4 etc.,

The ions of inert electrolyte do not react with other ions present in the half cells and they are not either oxidised (or) reduced at the electrodes. The solution in the salt bridge Voltmeter
cannot get poured out, but through which the ions can move into (or) out of the half cells. When the switch (k) closes the circuit, the electrons flows from zinc strip to copper strip. This is due to the following redox reactions which are taking place at the respective electrodes.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-11

Anodic oxidation:
The electrode at which the oxidation occur is called the anode. In Daniel cell, the oxidation take place at zinc electrode, i.e., zinc is oxidised to Zn2 ions and the electrons. The Zn2 ions enters the solution and the electrons enter the zinc metal, then flow through the external wire and then enter the copper strip. Electrons are liberated at zinc electrode and hence it is negative ( – ve).
Zn(s) → Zn2+(aq) + 2e (loss of electron-oxidation)

Cathodic reduction:
As discussed earlier, the electrons flow through the circuit from zinc to copper, where the Cu2+ ions in the solution accept the electrons, get reduced to copper and the same get deposited on the electrode. Here, the electrons are consumed and hence it is positive (+ve).
Cu2+(aq) + 2e → Cu(s) (gain of electron-reduction)

Salt bridge:
The electrolytes present in two half cells are connected using a salt bridge. We have learnt that the anodic oxidation of zinc electrodes results in the increase in concentration of Zn2+ in solution. i.e., the solution contains more number of Zn2+ ions as compared to SO42- and hence the solution in the anodic compartment would become positively charged.

Similarly, the solution in the cathodic compartment would become negatively charged as the Cu2+ ions are reduced to copper i.e., the cathodic solution contain more number of SO2-4 ions compared to Cu2+.

Completion of circuit:
Electrons flow from the negatively charged zinc anode into the positively charged copper electrode through the external wire, at the same time, anions move towards anode and cations are move towards the cathode compartment. This completes the
circuit.

Consumption of Electrodes:
As the Daniel cell operates, the mass of zinc electrode gradually decreases while the mass of the copper electrode increases and hence the cell will function until the entire metallic zinc electrode is converted in to Zn2+ the entire Cu2+ ions are converted in to metallic copper.
Daniel cell is represented as
Zn(s)|Zn2+(aq)||Cu2+(aq)|Cu(s)

Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-12

Question 7.
Why is anode in galvanic cell considered to be negative and cathode positive electrode?
Answer:
A galvanic cell works basically in reverse to an electrolytic cell. The anode is the electrode where oxidation takes place, in a galvanic cell, it is the negative electrode, as when oxidation occurs, electrons are left behind on the electrode.

The anode is also the electrode where metal atoms give up their electrons to the metal and go into solution. The electron left behind on it render ¡t effectively negative and the electron flow goes from it through the wire to the cathode.

Positive aqueous ions in the solution are reduced by the incoming electrons on the cathode. This why the cathode is a positive electrode, because positive ions are reduced to metal atoms there.

Question 8.
The conductivity of a 0.01%M solution of a 1:1 weak electrolyte at 298K is 1.5 x 10-4 S cm-1.

  1. molar conductivity of the solution
  2. degree of dissociation and the dissociation constant of the weak electrolyte

Given that
λ0cation = 248.2 S cm2 mol-1
λ0anion = 51.8 S cm2 mol-1
Answer:
1. Molar conductivity
C = 0.01M
k = 1.5 x 10-4 S cm-1
(or)
K = 1.5 x 10-2 S m-1
\(\frac{\kappa \times 10^{-3}}{\mathrm{C}}\) S m-1 mol-1 m3 = \(\frac{1.5 \times 10^{-2} \times 10^{-3}}{0.01}\) S m2 mol-1
Λm = 1.5 x 10-3 s m-1

2. Degree of dissociation
α = \(\frac{\Lambda_{\mathrm{m}}}{\Lambda_{\infty}^{\circ}}\) (or) α = \(\frac{\Lambda_{\mathrm{m}}}{\Lambda_{\mathrm{m}}^{\circ}}\)
= (248.2 + 51.8)S cm2 mol-1
= 300 S cm2 mol-1
Ka = \(\frac{\alpha^{2} C}{1-\alpha}\)
= \(\frac{(0.05)^{2}(0.01)}{1-0.05}\)
Ka = 2.63 x 10-5

Question 9.
Which of 0.1M HCI and 0.1 M KCI do you expect to have greater molar conductance and why?
Answer:
Compare to 0.1M HCI and 0.1 M KCI, 0.1M HCl has greater molar conductance.

  1. Molar conductance of 0.1M HCl = 39.132 x 10-3 S m2 mol-1.
  2. Molar conductance of 0.1 M KCl = 12.896 x 10-3 S m2 mol-1

Because, H+ ion in aqueous solution being smaller size than K+ ion and H+ ion have greater mobility than K ion. When mobility of the ion increases, conductivity of that ions also increases. Hence, 0. 1M HCI solution has greater molar conductance than 0.1 M KCI solution.

Question 10.
Arrange the following solutions in the decreasing order of specific conductance.

  1. 0.01M KCI
  2. 0.005M KCI
  3. 0.1M KCI
  4. 0.25 M KCI
  5. 0.5 M KCI

Answer:
0.005M KCl > 0.01M KCI > 0.1M KCI > 0.25KCl > 0.5 KCI.
Specific conductance and concentration of the electrolyte. So if concentration decreases, specific conductance increases.

Question 11.
Why is AC current used instead of DC in measuring the electrolytic conductance?
Answer:
1. AC current to prevent electrolysis of the solution.

2. If we apply DC current to the cell the positive ions will be attracted to the negative plate and the negative ions to the positive plate. This will cause the composition of the electrolyte to change while measuring the equivalent conductance.

3. So DC current through the conductivity cell will lead to the electrolysis of the solution taken in the cell. To avoid such a electrolysis, we have to use AC current for measuring equivalent conductance.

Question 12.
0.1M NaCI solution is placed in two different cells having cell constant 0.5 and 0.25cm-1 respectively. Which of the two will have greater value of specific conductance.
Answer:
The specific conductance values are same. Because the reaction (cation) of cell constant does not change.

Question 13.
A current of 1 .608A is passed through 250 mL of 0.5M solution of copper sulphate for 50 minutes. Calculate the strength of Cu2+ after electrolysis assuming volume to be constant and the current efficiency is 100%.
Answer:
Given, I = I .608A
t = 50 min (or) 50 x 60 = 3000 S
V = 250 mL
C = 0.5M
η = 100%
The number of Faraday’s of electricity passed through the CuSO4 solution
Q = It
= Q = 1.608 x 3000
Q = 4824C
Number of Faraday’s of electricity = \(\frac { 4824C }{ 96500C }\) = 0.5F
Electrolysis of CuSO4
Cu2+(aq) + 2e → Cu(s)
The above equation shows that 2F electricity will deposit 1 mole of Cu2+
0.5F electicity will deposit \(\frac { 1mol }{ 2F }\) x 0.5F = 0.025 mol
Initial number of molar of Cu2+ in 250 ml of solution = \(\frac { 1mol }{ 250mL }\) x 250mL = 0.125 mol
Number of molar of Cu2+ after electrolysis 0.125 – 0.025 = 0.1 mol
Concentration of Cu2+ = \(\frac { 0.1mol }{ 250mL }\) X 1000 mL = 0.4 M

Question 14.
Can Fe3+ oxidises Bromide to bromine under standard conditions?
Given:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-58
Answer:
Required half cell reaction
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-59
E0cell = (E0ox) + (E0red) = – 1.09 + 0.771 = – 0.319V
We know that ∆G° = – nFE0cell
If E0cell is -ve; ∆G is +ve and the cell reaction is non-spontaneous.
Hence, Fe3+ cannot oxidise Bromide to Bromine.

Question 15.
Is it possible to store copper sulphate in an iron vessel for a long time?
Given:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-60
Answer:
E0cell = (E0ox) + (E0red) = 0.44 V + 0.34V = 0.78V
These +ve E0cell values shows that iron will oxidise and copper will get reduced i.e., the vessel
will dissolve. Hence it is not possible to store copper sulphate in an iron vessel.

Question 16.
Two metals M1 and M2 have reduction potential values of – xV and + yV respectively. Which will liberate H2 in H2SO4?
Answer:
Metals having negative reduction potential acts as powerful reducing agent. Since M1 has – xV, therefore M1 easily liberate H2 in H2SO4. Metals having higher oxidation potential will liberate H2 from H2SO4. Hence, the metal M1 having + xV, oxidation potential will liberate H2 from H2SO4.

Question 17.
Reduction potential of two metals M1 and M2 are
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-13
Predict which one Is better for coating the surface of iron.
Given:Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-61
Answer:
Oxidation potential of M1 is more +ve than the oxidation potential of Fe which indicates that it will prevent iron from rusting.

Question 18.
Calculate the standard emf of the cell: Cd | Cd2+|| Cu2+ | Cu and determine the cell reaction. The standard reduction potentials of Cu2+ | Cu and Cd2+ | Cd are 0.34V and – 0.40 volts respectively. Predict the feasibility of the cell reaction.
Answer:
Cell reactions:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-14
Cd(s) + 2e Cd2+ + Cu(s)
E0cell = (E0ox) + (E0red) = 0.4 + 0.34
emf is +ve, so ∆G is (-)ve, the reaction is feasible.

Question 19.
In fuel cell H2 and O2 react to produce electricity. In the process, H2 gas is oxidised at the anode and O2 at cathode. If 44.8 litre of H2 at 25°C and also pressure reacts in 10 minutes, what is average current produced? If the entire current is used for electro deposition of Cu from Cu2+, how many grams of Cu deposited?
Answer:
Oxidation at anode:
2H2(g) + 4OH (aq) → 4H2O (1) + 4e
1 mole of hydrogen gas produces 2 moles of electrons at 25°C and 1 atm pressure, 1 mole of hydrogen gas occupies = 22.4 litres
∴no. of moles of hydrogen gas produced = \(\frac{1 \mathrm{mole}}{22.4 \text { litres }}\) x 44.8 litres = 2 moles of hydrogen
∴2 of moles of hydrogen produces 4 moles of electro i.e., 4F charge. We know that Q = It
I = \(\frac { Q }{ t }\) = \(\frac{4 \mathrm{F}}{10 \mathrm{mins}}\) = \(\frac { 4×96500 }{ 10x60s }\)
I = 643.33 A
Electro deposition of copper
Cu2+(aq) + 2e → Cu(s)
2F charge is required to deposit
1 mole of copper i.e., 63.5 g
If the entire current produced in the fuel cell i.e., 4 F is utilised for electrolysis, then 2 x 63.5 i.e., 127.0 g copper will be deposited at cathode.

Question 20.
The same amount of electricity was passed through two separate electrolytic cells containing solutions of nickel nitrate and chromium nitrate respectively. If 2.935g of Ni was deposited in the first cell. The amount of Cr deposited in the another cell? Given: molar mass of Nickel and chromium are 58.74 and 52gm-1 respectively.
Answer:
Ni2+ (aq) + 2e → Ni (s)
Cr2+(aq) + 3e → Cr(s)
The above reaction indicates that 2F charge is required to deposit 58.7 g of Nickel form nickel nitrate and 3F charge is required to deposit 52g of chromium. Given that 2.935 gram of Nickel is deposited 2F
The amount of charge passed through the cell = \(\frac { 2F }{ 58.7g }\) x 2.935g = 0.1F
If 0. IF charge is passed through chromium nitrate the amount of chromium deposited
= 52g x 0.IF = 1.733g

Question 21.
0.1M copper sulphate solution in which copper electrode is dipped at 25C. Calculate the electrode potential of copper.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-62
Answer:
Given that
[Cu2+] = 0.1 M
E0Cu2+|Cu = 0.34
Ecell = ?
Cell reaction is Cu2+(aq) + 2e → Cu (s)
Ecell = E0 – \(\frac { 0.0591 }{ n }\) log \(\frac{[\mathrm{Cu}]}{\left[\mathrm{Cu}^{2+}\right]}\) = 0.34 – \(\frac { 0.0591 }{ 2 }\) log \(\frac { 1 }{ 0.1 }\)
= 0.34 – 0.0296 = 0.31 V

Question 22.
For the cell Mg(s) | Mg2+(aq) || Ag+ (aq) | Ag (s), calculate the equilibrium constant at 25°C and maximum work that can be obtained during operation of cell. Given:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-63
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-15
E0cell = (E0ox) + (E0red) = 2.37 + 0.80 = 3.17 V
Overall reaction
Mg + 2Ag+ → Mg2+ + 2Ag
∆G° = -nFE°
= – 2 x 96500 x 3.17
= – 6.118 x 105 J
We know that Wmax = ∆G°
Wmax = + 6.118 x 105 J
Relationship between ∆G° and Keq is,
∆G = – 2.303 RT logKeq
∆G = – 2.303 x 8.314 x 298 log Keq [25°C = 298 K]
log Keq = \(\frac{6.118 \times 10^{5}}{2.303 \times 8.314 \times 298}\) = \(\frac{6.118 \times 10^{5}}{5705.84}\)
log Keq = 107.223
Keq = Antilog (107.223)

Question 23.
8.2 x 1012 litres of water is available in a lake. A power reactor using the electrolysis of water in the lake produces electricity at the rate of 2 x 106 Cs-1 at an appropriate voltage. How many years would it like to completely electrolyse the water in the lake. Assume that there is no loss of water except due to electrolysis.
Answer:
Hydrolysis of water:
At anode: 2H2O → 4H+ + O2 + 4e …………..(1)
At cathode: 2H2O + 2e → H2 + 2OH
Overall reaction: 6H2O → 4H + 4OH +2H2 + O2
(or)
Equation (1) + (2) x 2
= 2H2O → 2H2 + O2
According to Faraday’s Law of electrolysis, to electrolyse two mole of Water
(36g ≃ 36 mL. of H2O), 4F charge is required alternatively, when 36 mL of water is electrolysed,
the charge generated = 4 x 96500 C.
When the whole water which is available on the lake is completely electrolysed the amount of charge generated is equal to
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-16
Given that in 1 second, 2 x 106 C is generated therefore, the time required to generate
96500 x 1015 C is = \(\frac{1 \mathrm{S}}{2 \times 10^{6} \mathrm{C}}\) x 96500 x 1015C = 48250 x 109 S
Number of year = \(\frac{48250 \times 10^{9}}{365 \times 24 \times 60 \times 60}\) 1 year = 365 days
= 1.5299 x 106
= 365 x 24 hours
= 365 x 24 x 60 min
= 365 x 24 x 60 x 60 sec

Question 24.
Derive an expression for Nernst equation.
Answer:
Nernst equation is the one which relates the cell potential and the concentration of the species involved in an electrochemical reaction.
Let us consider an electrochemical cell for which the overall redox reaction is,
Answer:
xA + yB = lC + mD
The reaction quotient Q is,
\(\frac{[\mathrm{C}]^{1}[\mathrm{D}]^{\mathrm{m}}}{[\mathrm{A}]^{\mathrm{x}}[\mathrm{B}]^{\mathrm{y}}}\)
We know that,
∆G = ∆G0 + RT ln Q
∆G = – nFEcell
∆G0 = -nFE0cell
equation (1) becomes
– nFEcell = -nFE0cell + RT ln Q
Subsitute the Q value in equation (2)
– nFEcell = – nFE0cell + RT ln \(\frac{[\mathrm{C}]^{1}[\mathrm{D}]^{\mathrm{m}}}{[\mathrm{A}]^{\mathrm{x}}[\mathrm{B}]^{\mathrm{y}}}\). ………..(3)
Divide the whole equation (3) by – nF
Ecell = E°cell – \(\frac { RT }{ nF }\) ln \(\left(\frac{[\mathrm{C}]^{1}[\mathrm{D}]^{\mathrm{m}}}{[\mathrm{A}]^{\mathrm{x}}[\mathrm{B}]^{\mathrm{y}}}\right)\)
Ecell = E°cell – \(\frac { 2.303RT }{ nF }\) log \(\left(\frac{[\mathrm{C}]^{1}[\mathrm{D}]^{\mathrm{m}}}{[\mathrm{A}]^{\mathrm{x}}[\mathrm{B}]^{\mathrm{y}}}\right)\) ……………(4)
This is called the Nernst equation.
At 25°C (298 K) equation (4) becomes,
Ecell = E°cell – \(\frac { 2.303×8.314×298 }{ nx96500 }\) log \(\left(\frac{[\mathrm{C}]^{1}[\mathrm{D}]^{\mathrm{m}}}{[\mathrm{A}]^{\mathrm{x}}[\mathrm{B}]^{\mathrm{y}}}\right)\)
Ecell = E°cell – \(\frac { 0.0591 }{ n }\) log \(\left(\frac{[\mathrm{C}]^{1}[\mathrm{D}]^{\mathrm{m}}}{[\mathrm{A}]^{\mathrm{x}}[\mathrm{B}]^{\mathrm{y}}}\right)\)

Question 25.
Write a note on sacrificial protection.
Answer:
In this method, the metallic structure to be protected is made cathode by connecting it with more active metal (anodic metal). So that all the corrosion will concentrate only on the active metal. The artificially made anode thus gradually gets corroded protecting the original metallic structure. Hence this process is otherwise known as sacrificial anodic protection. Al, Zn and Mg are used as sacrificial anodes.

Question 26.
Explain the function of H2 – O2 fuel cell.
Answer:
In this case, hydrogen act as a fuel and oxygen as an oxidant and the electrolyte is aqueous KOH maintained at 200°C and 20 – 40 atm. Porous graphite electrode containing Ni and NiO serves as the inert electrodes. Hydrogen and oxygen gases are bubbled through the anode and cathode, respectively.
Oxidation occurs at the anode:
2H2(g)+ 4OH-(aq) → 4H2O(1) + 4e
Reduction occurs at the cathode O2(g) + 2 H2O(1) + 4e → 4 OH (aq)
The overall reaction is 2H2(g) + O2(g) → 2H2O(1)
The above reaction is the same as the hydrogen combustion reaction, however, they do not react directly ie., the oxidation and reduction reactions take place separately at the anode and cathode respectively like H2 – O2 fuel cell. Other fuel cell like propane – O2 and methane O2 have also been developed.

Question 27.
Ionic conductance at infinite dilution of Al3+ and SO42- are 189 and 160 mho cm2 equiv-1. Calculate the equivalent and molar conductance of the electrolyte Al2(SO4) at infinite dilution.
Answer:
1. Molar conductance
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-20
= (2 x 189) + (3 x 160)
= 378 + 480
= 858 mho cm2 mol-1

2. Equivalent conductnace
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-21
= \(\frac { 189 }{ 3 }\) + \(\frac { 160 }{ 2 }\)
= 143 mho cm2 (g equiv)-1

Samacheer Kalvi 12th Chemistry Electro Chemistry Evaluate Yourself

Question 1.
Calculate the molar conductance of 0.01M aqueous KCI solution at 25°C . The specific conductance of KCl at 25°C is 14.114 x 10-2 Sm-1.
Answer:
Concentration of KCI solution = 0.01 M.
Specific conductance (K) = 14.114 x 10-2 S m-1
Molar conductance (Λm) = ?
Λm = \(\frac{\kappa \times 10^{-3}}{M}\) = \(\frac{14.114 \times 10^{-2} \times 10^{-3}}{0.01}\)
S m-1 mol-1 m3
Λm = 14.114 x 10-5 x 102 = 14.114 x 10-3 Sm2 mol-1

Question 2.
The resistance of 0.15M solution of an electrolyte is 50. The specific conductance of the solution is 2.4 Sm-1. The resistance of 0.5 N solution of the same electrolyte measured using the same conductivity cell is 480Ω. Find the equivalent conductivity of 0.5 N solution of the electrolyte.
Answer:
Given that R1 = 50Ω
R2 = 480Ω
K1 =2.4Sm-1
K2 = ?
N1 = 0.15N
N2 = 0.5N
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-22
= 5 x 10-4sm2 gram equivalent-1
We know that
\(\frac{\text { Cell constant }}{\mathrm{R}}\)
\(\frac{\kappa_{2}}{\kappa_{1}}\) = \(\frac{R_{1}}{R_{2}}\)
k2 = k1 x \(\frac{R_{1}}{R_{2}}\) = 2.4 Sm-1 x \(\frac{50 \Omega}{480 \Omega}\) = 0.25 Sm-1

Question 3.
The emf of the following cell at 25°C is equal to 0.34v. Calculate the reduction potential of copper electrode.
Pt(s) | H2(g,1atm) | H+ (aq,1M) || Cu2+(aq,1M) | Cu(s)
Answer:
SHE Value is zero
cell = E°R – E°L
= 0.34 – 0 = 0.34V
The reduction potential of copper electrode = 0.34V

Question 4.
Using the calculated emf value of zinc and copper electrode, calculate the emf of the following cell at 25°C.
Zn (s) | Zn2+ (aq, 1M) || Cu2+(aq, 1M) | Cu (s)
Answer:
cell = E°R – E°L
Ezn/zn2+ = 0.76V
ECu/Cu2+ = 0.76V
cell = 0.76 – (- 0.34V)
cell = 0.76 – (- 0.34)
cell = + 1.1 V

Question 5.
Write the overall redox reaction which takes place in the galvanic cell,
Pt(s) | Fe2+(aq),Fe2+(aq) || MnO4(aq), H+(aq), Mn2+(aq) || Pt(s)
Answer:
At Anode half cell – 5Fe2+(aq) → 5Fe3+(aq) + 5e
At cathode half cell – MnO4(aq) + 8H+(aq) + 5e → Mn2+(aq) + 4H2O(1)
Overall redox reaction – 5Fe2+(aq) + MnO4(aq) + 8H+(aq) → 5Fe3+(aq) + Mn2+(aq) + 4H2O(1)

Question 6.
The electrochemical cell reaction of the Daniel cell is
Zn (s) + Cu2+(aq) → Zn2+(aq) + Cu(s)
What is the change in the cell voltage on increasing the ion concentration in the anode compartment by a factor 10?
Answer:
Zn (s) + Cu2+(aq) → Zn2+(aq) + Cu(s)
ln the case E°cell = 1.1V
Reaction quotient Q for the above reaction is, Q = \(\frac{\left[\mathrm{Zn}^{2+}\right]}{\left[\mathrm{Cu}^{2+}\right]}\)
Ecell = E°cell – \(\frac { 0.0591 }{ n }\) log \(\frac{\left[Z n^{2+}\right]}{\left[C u^{2+}\right]}\)
If suppose concentration of Cu2+ is 1 .OM then the concentration of Zn2+ is 10M (why because,
ion concentration in the anode compartment increased by a 10 factor)
Ecell = 1.1 – \(\frac { 0.0591 }{ n }\) log \((\frac { 10 }{ 1 })\)
= 1.1 – 0.02955             ……………….(1)
= 1.070 V (cell voltage decreased)
Thus, the initial voltage is greater than E° because Q < 1. As the reaction proceeds, [Zn2+] in the anode compartment increases as the zinc electrode dissolves, while [Cu2+] in the cathode compartment decreases as metallic copper is deposited on the electrode.

During this process, the Q = [Zn2+] [Cu2+] steadily increases and the cell voltage therefore steadily decreases. [Zn2+] will continue to increase in the anode compartment and [Cu2+] will continue to decrease in the cathode compartment. Thus the value of Q will increase further leading to a further
decrease in value.

Question 7.
A solution of a salt of metal was electrolysed for 150 minutes with a current of 0.15 amperes. The mass of the metal deposited at the cathode is 0.783g. calculate the equivalent mass of the metal.
Answer:
Given,
I = 0.15 amperes
t = 150 mins
= t = 15O x 6Osec
= t = 9000sec
Q = It
= Q = 0.15 x 9000 coulombs
= Q = 1350 coulombs
Hence, 135 coulombs of electricity deposit is equal to 0.783g of metal.
96500 coulombs of electricity, \(\frac { 0.783 x 96500 }{ 1350 }\) = 55.97 gm of metal
Hence equivalent mass of the metal is 55.97

Samacheer Kalvi 12th Chemistry Electro Chemistry Example Problems

Question 1.
A conductivity cell has two platinum electrodes separated by a distance 1.5 cm and the cross sectional area of each electrode is 4.5 sq cm. Using this cell, the resistance of 0.5 N electrolytic solution was measured as 15?. Find the specific conductance of the solution.
Solution.
k = \(\frac { 1 }{ 15Ω }\) x \(\frac{1.5 \times 10^{-2} \mathrm{m}}{4.5 \times 10^{-4} \mathrm{m}^{2}}\) = 2.22S m-1
l = 1.5cm = 1.5 x 102m
A = 4.5 cm2 x (10-4)m2
R = 15Ω

Question 2.
Calculate the molar conductance of 0.025M aqueous solution of calcium chloride at 25°C. The specific conductance of calcium chloride is 12.04 x 102S m3.
Answer:
Molar conductance
Λm = \(\frac{\left(\mathrm{Sm}^{-1}\right) \times 10^{-3}}{\mathrm{M}}\) mol-1 m3
= \(\frac{\left(12.04 \times 10^{-2} \mathrm{Sm}^{-1}\right) \times 10^{-3}}{0.025}\) mol-1 m3 = 581 . 6 10-2 S m2 mol1

Question 3.
The resistance of a conductivity cell is measured as 190Ω using 0.1M KCI solution (specific conductance of 0.1M KCI is 1.3 Sm-1). When the same cell is filled with 0.003M sodium chloride solution, the measured resistance is 6.3K?. Both these measurements are made at a particular temperature. Calculate the specific and molar conductance of NaCl solution.
Answer:
Given that
K = 1.3 S m-1 (for 0.1 M KCI solution)
R = 190Ω
\(\left(\frac{l}{A}\right)\) = k.R = (1.3 S m-1) (190?) = 247m-1
k(NaCl) = \(\frac{1}{\mathrm{R}_{(\mathrm{NaCT})}}\)\(\left(\frac{l}{A}\right)\) = \(\frac{1}{6.3 \mathrm{K} \Omega}\) (247m-1)
= 39.2 x 10-3Sm-1
Λm = \(\frac{\kappa \times 10^{-3} \mathrm{mol}^{-1} \mathrm{m}^{3}}{\mathrm{M}}\) = \(\frac{39.2 \times 10^{-3}\left(\mathrm{Sm}^{-1}\right) \times 10^{-3}\left(\mathrm{mol}^{-1} \mathrm{m}^{3}\right)}{0.003}\)
Λm = 13.04 x 10-3Sm2 mol-1

Question 4.
The net redox reaction of a galvanic cell is given below
2 Cr (s) + 3Cu2+(aq) → 2Cr3+(aq) + 3Cu(s)
Write the half reactions and describe the cell using cell notation.
Answer:
Anodic oxidation: 2Cr(s) → 2Cr3+(aq) + 6e …………..(1)
Cathodic reduction: 3Cu2+ + 6e → 3Cu(s) ………….(2)
Cell Notation is: Cr(s) | CI3+(aq) || Cu2+(aq) | Cu(s)

Question 5.
Let us calculate the emf of the following cell at 25°C using Nernst equation.
Cu (s) | Cu2+(0.25 aq, M) || Fe3+(0.05 aq M) | Fe2+(0.1 aq M) | pt(s)
Answer:
Given: Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-25
Half reactions are
Cu (s) → Cu2+(aq) + 2e ……………(1)
2 Fe3+(aq) + 2e → 2Fe2+(aq) ……………(2)
the overall reaction is Cu (s) + 2 Fe3+(aq) → Cu2+(aq) + 2Fe2+(aq), and n = 2
Apply Nernst equation at 25°C
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-26
Given standard reduction potetial of Cu2+ | Cu is o.34
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-64

Question 6.
A solution of silver nitrate Is electrolysed for 20 minutes with a current of 2 amperes. Calculate the mass of silver deposited at the cathode.
Answer:
Electrochemical reaction at cathode is Ag+ + e Ag (reduction)
m = ZIt
m = \(\frac{108 \mathrm{gmol}^{-1}}{96500 \mathrm{Cmol}^{-1}} \times 2400 \mathrm{C}\)
m = 2.68 g
z = \(\frac{\text { molarmass of } \mathrm{Ag}}{(96500)}\) = \(\frac{108}{1 \times 96500}\)
I = 2Ag
t = 20 x 60s = 1200s
It = 2A x 1200S = 2400C

Samacheer Kalvi 12th Chemistry Electro Chemistry Additional Questions

Samacheer Kalvi 12th Chemistry Electro Chemistry 1 Marks Questions And Answers

I. Choose the best answer and write it.

Question 1.
Which one of the following is an example of conductor?
(a) PVC
(b) Bakelite
(c) Aluminium
(d) Rubber
Answer:
(c) Aluminium

Question 2.
Which one of the following can act as an insulator?
(a) Bakelite
(b) Aluminium
(c) Copper
(d) NaCI Solution
Answer:
(a) Bakelite V

Question 3.
Which form of energy is converted to electrical energy in batteries?
(a) tidal energy
(b) Chemical energy
(c) mechanical energy
(d) atomic energy
Answer:
(b) Chemical energy

Question 4.
Electro chemical reactions are generally ………..
(a) Reduction reactions
(b) oxidation reactions
(c) Redox reactions
(d) condensation reactions
Answer:
(c) Redox reactions

Question 5.
Consider the following statements.
Answer:
(i) Energy can neither be created nor be destroyed but one form of energy can be converted to another form
(ii) In batteries, electrical energy is converted to chemical energy.
(iii) Electrochemjcal reactions are redox reactions.

Which of the above statement is / are not correct?
(a) i & ii only
(b) ii only
(c) i only
(d) iii only
Answer:
(b) ii only

Question 6.
Which one of the following represents Ohm’s law?
(a) V = IR
(b) R = \(\frac { 1 }{ V }\)
(c) I = \(\frac { V }{ R }\)
(d) R = VI
Answer:
(a) V = IR

Question 7.
The unit of resistivity is …………
(a) Ω m-1
(b) Ω m
(c) m-1Ohm2
(d) Ω-1m-1
Answer:
(b) Ω m

Question 8.
When cell constant is unit, the resistance is known as …………
(a) specific resistance
(b) conductance
(c) specific conductance
(d) equivalent conductance
Answer:
(a) specific resistance

Question 9.
The unit of specific resistance is equal to ………..
(a) Ohm metre
(b) Ohm-1 metre
(c) Ohm-1 metre-1
(d) Ohm
Answer:
(a) Ohm metre

Question 10.
Which is the SI unit of conductance?
(a) Siemen-1 (or) S-1
(b) Siemen (or) S
(c) Sm-1
(d) S-1m-1
Answer:
(b) Siemen (S)

Question 11.
Which one of the following represents specific conductance (kappa)?
(a) \(\frac { I }{ C }\) . \(\frac { l }{ a }\)
(b) \(\frac { I }{ P }\) . \(\frac { a }{ I }\)
(c) \(\frac { 1 }{ 2 }\) . \(\frac{a}{l^{2}}\)
(d) \(\frac { I }{ P }\) . \(\frac { l }{ a }\)
Answer:
(d) \(\frac { I }{ P }\) . \(\frac { l }{ a }\)

Question 12.
Which one is the unit of specific conductance?
(a) Ohm m
(b) Ohm-1 m
(c) Ohm m-1
(d) Ohm-1 m-1.
Answer:
(d) Ohm-1m-1

Question 13.
Which one of the following formula represents equivalent conductance?
(a) \(\frac { I }{ P }\).\(\frac { l }{ a }\)
(b) \(\frac { I }{ P }\).\(\frac { A }{ l }\)
(c) C x \(\frac { l }{ a }\)
(d) \(\frac{\kappa \times 10^{-3}}{N}\)
Answer:
(d) \(\frac{\kappa \times 10^{-3}}{N}\)

Question 14.
The unit of equivalent conductance is …………
(a) Sm2g equivalenr’
(b) Sm-1
(c) Ohm-1m-1
(d) Ohm m
Answer:
(a) Sm2g equivalent-1

Question 15.
Consider the following statements:
(i) Solvent of higher dielectric constant show very low conductance in solution.
(ii) Conductance is directly proportional to viscosity of the medium.
(iii) Molar conductance of a solution increases with increase in dilution.
Which of the above statement is / are correct?
(a) (i) & (ii)
(b) (ii) and (iii)
(c) (iii) only
(d) (i) only
Answer:
(c) (iii) only

Question 16.
Consider the following statements:
(i) If the temperature of the electrolytic solution increases, conductance decreases.
(ii) Conductivity increases with the decrease in viscosity.
(iii) Molar conductance of a solution decreases with increase in dilution.
Which of the above statement is / are not correct?
(a) (i) & (iii)
(b) (i) and (ii)
(c) (iii) only
(d) (ii) only
Answer:
(a) (i) & (iii)

Question 17.
Which one of the following is used to measure conductivity of ionic solutions?
(a) metre scale
(b) wheat stone bridge
(c) Dynamo
(d) Ammeter
Answer:
(b) wheat stone bridge

Question 18.
Which of the following is used to calculate the conductivity of strong electrolytes?
(a) Kohlraush’s law
(b) Henderson equation
(c) Debye-Huckel and Onsagar equation
(d) Ostwald’s dilution law
Answer:
(c) Debye-Huckel and Onsagar equation

Question 19.
Which one of the following represents Debye-Huckel and Onsagar equation?
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-28
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-29

Question 20.
The value of A in Debye – Huckel and Onsagar equation is ……….
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-30
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-31

Question 21.
The value of B in Debye Huckel and onsagar equation is …………
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-32
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-33

Question 22.
Kohlrausch’s law is applied to calculate
(a) molar conductance at infinite dilution of a weak electrolyte
(b) degree of dissociation of weak electrolyte
(c) solubility of a sparingly soluble salt
(d) all the above
Answer:
(d) all the above

Question 23.
In which of the following interconversion of electrical energy into chemical energy and vice versa take place?
(a) electrochemical cell
(b) electric cell
(c) Dynamo
(d) AC generator
Answer:
(a) electrochemical cell

Question 24.
Consider the following statements:
(i) In Galvanic cell, chemical energy is’converted into electrical energy.
(ii) In electrolytic cell, electrical energy is converted into chemical energy.
(iii) In voltaic cell, electrical energy is converted into chemical energy.

Which of the above statement is / are not correct?
(a) (i) & (ii)
(b) (iii) only
(c) (ii) only
(d) (i) only
Answer:
(b) (iii) only

Question 25.
In Galvanic cell, the Zinc metal strip placed gets ………….
(a) Oxidised
(b) reduced
(c) hydrolysed
(d) condensed
Answer:
(a) Oxidised

Question 26.
Consider the following statements:
(i) In Galvanic cell, Zinc is oxidised to Zn2+ ions and Cu2+ ions are reduced to copper
(ii) In Galvanic cell, Zn2+ ions are reduced to Zinc and copper is oxidised to Cu2+ ions
(iii) In Galvanic cell, Zn and copper both get oxidised.
Which of the above statement is / are correct?
(a) (i) only
(b) (ii) & (iii)
(c) (ii) only
(d) (iii) only
Answer:
(a) (i) only

Question 27.
The salt bridge used in Daniel cell contains
(a) Na2SO4 + NaCl
(b) Agar-Agar gel + Na2SO4
(c) Silica gel + CuSO4
(d) ZnSO4 + CuSO4
Answer:
(b) Agar-Agar gel + Na2SO4

Question 28.
Consider the following statements.
(i) In Daniel cell, when the switch (k) closes the circuit, the electrons flow from Zinc strip to copper strip.
(ii) In Daniel cell, when the switch (k) closes the circuit, the electrons flow from copper strip to Zinc strip
(iii) In Daniel cell, when the Switch (k) opens the circuit, the electrons flow from Zinc to copper.
Which of the above statement is / are correct?
(a) (i) only
(b) (ii) & (iii)
(c) (ii) only
(d) (iii) only
Answer:
(a) (i) only

Question 29.
Which one of the following can act as an inert electrode?
(a) Graphite
(b) Copper
(c) Platinum
(d) either a (or) e
Answer:
(a) either a (or) c

Question 30.
The SI unit of cell potential is ………….
(a) Ampere
(b) Ohm
(c) Volt
(d) Ohm-1
Answer:
(c) Volt

Question 31.
The emf of Daniel cell Zn(s) + Zn2+aq(1m) || Cu2+aq(1m) | Cu(S) iS equal to …………
(a) – 1.107 Volts
(b) 1.107 Volts
(c) 3.4 Volt
(d) 7.6 Volt
Answer:
(b) 1.107 Volts

Question 32.
Which instrument is used to measure potential difference?
(a) Ammeter
(b) Voltmeter
(c) Wheat stone bridge
(d) metre bridge
Answer:
(b) Voltmeter

Question 33.
The value of EMF of standard hydrogen electrode at 25°C is …………
(a) maximum
(b) zero
(c) negative
(d) positive
Answer:
(b) zero

Question 34.
The electrode used in SHE is made of ………….
(a) graphite
(b) copper
(c) platinum
(d) iron
Answer:
(c) Platinum

Question 35.
What is the charge of one electron?
(a) 1.602 x 1019C
(b) 1.6 x 10-19C
(c) 9645C
(d) 96488C
Answer:
(b) 1.6 x 10-19C

Question 36.
The maximum work that can be obtained from a galvanic cell is ………..
(a) + nFE
(b) – nFE
(c) 2F
(d) 96500 F
Answer:
(b) – nFE

Question 37.
For all spontaneous cell reactions, the value of ?G should be ………….
(a) constant
(b) zero
(c) negative
(d) positive
Answer:
(c) negative

Question 38.
The value of one Faraday is equal to …………..
(a) 96400 C
(b) 96500 C
(c) 1 .602 x 10-19C
(d) 1 .602 x 1019C
Answer:
(b) 96500 C

Question 39.
The relationship between standard free energy change and equilibrium constant is expressed as ………..
(a) ΔG° = -RTInkeq
(b) ΔG = RTlnkeq
(c) ΔG° = \(-\frac{1}{\mathrm{RT} \ln \mathrm{k}_{\mathrm{eq}}}\)
(d) ΔG = RTlogeq
Answer:
(a) ΔG° -RThilc

Question 40.
Which equation relates the cell potential and the concentration of the species involved in an electro chemical reaction?
(a) Henderson equation
(b) Arrhenius equation
(c) Debye Huckel Onsagar equation
(d) Nemst equation
Answer:
(a) Nernst equation

Question 41.
Which one of the following is Nernst equation.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-34
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-35

Question 42.
Gibbs free energy can be related to cell emf as follows.
(a) ΔG° = – nFEcell
(b) ΔG° = – nFE°cell
(c) ΔG = nFEcell
(d) ΔG° = nFE°cell
Answer:
(b) ΔG° = – nFE°cell

Question 43.
Which one of the following represents Faraday’s first law?
(a) m = ZIt
(b) m = \(\frac { Z }{ It }\)
(c) m = \(\frac { It }{ Z }\)
(d) Z = mIt
Answer:
(a) m = ZIt

Question 44.
When 1 coulomb of electric current is passed the amount of substance deposited or liberated is known as ………..
(a) equivalent mass
(b) electro chemical equivalent
(c) molar mass
(d) 1 Faraday
Answer:
(b) electro chemical equivalent

Question 45.
The value of electro chemical equivalent is equal to ………..
(a) \(\frac{96500}{\text { Equivalent mass }}\)
(b) \(\frac{96500}{\text { Molar mass }}\)
(c) \(\frac{\text { Molar mass }}{96500}\)
(d) \(\frac{\text { Equivalent mass }}{96500}\)
Answer:
(d) \(\frac{\text { Equivalent mass }}{96500}\)

Question 46.
The mathematical expression of Faraday’s second law is …………
(a) m = ZIt
(b) \(\frac{m_{1}}{E_{1}}=\frac{m_{2}}{E_{2}}=\frac{m_{3}}{E_{3}}\)
(c) \(\frac{m_{1}}{Z_{1}}=\frac{m_{2}}{Z_{2}}=\frac{m_{3}}{Z_{3}}\)
(d) \(Z=\frac{m}{I t}\)
Answer:
(c) \(\frac{m_{1}}{Z_{1}}=\frac{m_{2}}{Z_{2}}=\frac{m_{3}}{Z_{3}}\)

Question 47.
Which one of the following is used in cell phone, dry cell in flashlight?
(a) Zn – Cu battery
(b) Li – ion battery
(c) Ag – Cu battery
(d) Na, NaCI battery
Answer:
(b) Li – ion battery

Question 48.
The primary batteries are ………..
(a) rechargeable
(b) non – rechargeable
(c) reversible
(d) renewable
Answer:
(b) non – rechargeable

Question 49.
Consider the following statements.
(i) The secondary batteries are rechargeable
(ii) Primary batteries are non – rechargeable
(iii) Batteries are used as a source of AC current at a constant voltage.
Which of the above statement is I are not correct?
(a) (i) & (ii)
(b) (iii) only
(c) (i) only
(d) (ii) only
Answer:
(b) (iii) only

Question 50.
The anode and cathode used in Leclanche cell are ………… respectively.
(a) Zinc, Graphite rod with MnO2
(b) Graphite rod in MnO2 and Zinc container
(c) Zn container and copper rod
(d) Copper container and Zinc rod
Answer:
(a) Zinc, Graphite rod with MnO2

Question 51.
Which electrolyte is used in Leclanche cell?
(a) ZnSO4 + CuSO4
(b) NH4CI + ZnCl2
(c) NaCI + CuSO4
(d) MnSO4 + MnO2
Answer:
(b) NH4Cl + ZnCl2

Question 52.
Which one of the following is used as cathode in Mercury button cell?
(a) Zinc
(b) Copper
(c) Zinc amalgamated with mercury
(d) HgO mixed with graphite
Answer:
(c) Zinc amalgamated with mercury

Question 53.
Which one of the following is used as anode in Mercury button cell?
(a) HgO mixed with graphite
(b) Zinc amalgamated with mercury
(c) Copper amalgamated with Mercury
(d) HgO mixed with Copper
Answer:
(a) HgO mixed with graphite.

Question 54.
The value of cell emf of Mercury button cell is ………..
(a) 1.35V
(b) – 076V
(c) 0.34V
(d) 100V
Answer:
(a) 1.35 V
Which one of the following is used in pacemakers, cameras and electronic watches?
(a) Li-ion battery
(b) Leclanche cell
(c) Galvanic cell
(d) Mercurry button cell
Answer:
(d) Mercury button cell

Question 56.
The electrolyte used in Mercury button cell is ………….
(a) Paste of kOH and ZnO
(b) CuSO4 + ZnSO4
(c) NaCl + MgCl2
(d) NH4CI + ZnCl2
Answer:
(a) Paste of kOH and ZnO

Question 57.
Which of the following is an example of secondary batteries?
(a) Mercury button cell
(b) Leclanche cell
(c) Lead storage battery
(d) Daniel cell
Answer:
(c) Lead storage battery

Question 58.
Which of the following act as cathode and anode in Lead storage battery?
(a) Lead plate bearing PbO2, spongy Lead
(b) Spongy lead, lead plate bearing PbO2
(c) Lead Copper
(d) Mercury oxide, PbO
Answer:
(a) Lead plate bearing PbO2, Spongy lead

Question 59.
Which one of the following is used as an electrolyte Lead storage battery?
(a) PbSO4
(b) H2SO4
(c) CuSO4
(d) HNO3
Answer:
(b) H2SO4

Question 60.
The emf of lead storage battery is …………
(a) +1.1 V
(b) 2.4V
(c) 2V
(d) 11 . 2V
Answer:
(c) 2 V

Question 61.
The Lead storage battery is used in …………
(a) pacemakers
(b) automobiles
(c) electronic watches
(d) flash light
Answer:
(b) automobiles

Question 62.
Which one of the following is used in automobiles, trains and in inverters?
(a) Lithium ion battery
(b) Mercurry button cell
(c) Lead storage battery
(d) Leclanche cell
Answer:
(c) Lead storage battery

Question 63.
Which one of the following is used as an anode in Lithium ion battery?
(a) Porous graphite
(b) Lithium
(c) CoO2
(d) Copper
Answer:
(a) Porous graphite

Question 64.
which one of the following is used as cathode in Lithium ion battery?
(a) Porous graphite
(b) Lithium
(c) CoO2
(d) Chromium
Answer:
(c) CoO2

Question 65.
Which one of the following is used in cellular phones, Laptop computers and in digital camera?
(a) Mercury button cell
(b) Lithium – ion battery
(c) H2O2 fuel cell
(d) Leclanche cell
Answer:
(b) Lithium – ion battery

Question 66.
Which one of the following is used as an electrolyte in H2O2 fuel cell?
(a) Aqueous CuSO4
(b) Aqueous CoO2
(c) Aqueous KOH
(d) NH4CI + ZnCI2
Answer:
(c) Aqueous KOH

Question 67.
Which one of the following is an example for electrochemical process?
(a) Chrome plating
(b) Rusting of iron
(c) Galvanisation
(d) All the above
Answer:
(a) All the above

Question 68.
The formula of rust is ………..
(a) Fe2O3
(b) Fe2O3.xH2O
(c) FeO
(d) FeO.xH2O
Answer:
(b) Fe2O3.xH2O

Question 69.
Which one of the following is / are very important for rusting’?
(a) Oxygen
(b) Water
(c) Both a & b
(d) H2O
Answer:
(c) Both a & b

Question 70.
The electro plating of Zinc over a metal is called …………..
(a) Electrolysis
(b) Redox reaction
(c) Galvanisation
(d) Passivation
Answer:
(c) Galvanisation

Question 71.
Consider the following statements.
(i) The standard reduction potential (E°) is a measure of oxidising tendency of the species.
(ii) The standard oxidation potential (E°) is a measure of oxidising tendency of the species.
(iii) The standard oxidation potential (E°) is a measure of redox tendency of the species.
Which of the above statement is / are not correct?
(a) (i) only
(b) (ii) only
(c) (ii) & (iii)
(d) (iii) only
Answer:
(c) (ii) & (iii)

Question 72.
On the basis of the electrochemical theory of aqueous corrosion, the reaction occuring at the cathode is …………
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-65
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-66
Hint:
2H+(aq) + 2e → 2H2
2H+ + \(\frac { 1 }{ 2 }\)O2 → H2O
2H+ + \(\frac { 1 }{ 2 }\)O2 +2e → H2O
Balancing the above equation
4H+(aq) + O2 + 4e → 2H2O

Question 73.
The standard reduction potential for the half reactions are as ………..
Zn → Zn2+ + 2e E° = +0.76V
Fe → Fe2+ + 2eE° = + 041 V.
So for cell reaction F2+ + Zn → Zn2+ + Fe is ………….
(a) – 0.35V
(b) +0.35V
(c) +1.17V
(d) – 1.117V
Answer:
(b) +0.35V
Hint:
In the reaction F2+ + Zn° → Zn2+ + Fe°
emf = Ecathode – Eanode
= – 0.41 – (- 0.76)
= – 0.41 + 0.76
emf = + 0.35V

Question 74.
The standard emf for the given cell reaction Zn + Cu2+ → Cu + Zn2+ is 1.10V at 25°C. The emf for the cell reaction when 0.1 M Cu2+ and 0.1 M Zn2+ solutions are used at 25°C is ……….
(a) 1.10V
(b) 0.110V
(c) – 1.10V
(d) – 110V
Answer:
(a) 1.10V
Hint:
Ecell = E°cell – \(\frac { 0.0592 }{ 2 }\) log\(\frac{\left(Z n^{2+}\right)}{\left(C u^{2+}\right)}\)
= 1.10 – \(\frac { 0.0592 }{ 2 }\) log \(\frac { 0.1 }{ 0.1 }\)
= 1.10 – \(\frac { 0.0592 }{ 2 }\) log 1
= 1.10 – \(\frac { 0.0592 }{ 2 }\) x 0
= 1.10V

Question 75.
Which amount of chlorine gas liberated at anode, if 1 ampere current is passed for 30 minutes from NaCI solution?
(a) 0.66 moles
(b) 0.33 moles
(c) 0.66 g
(d) 0.33 g
Answer:
(c) 0.66 g
Hint:
2Cl → Cl2 + 2e
Q = It.
Amount of current passed = 1 x 30 x 60 = 1800C
The amount of Cl2 liberated by passing 1800 coulomb of electric charge
= \(\frac{1 \times 1800 \times 71}{2 \times 96500}\)
= 0.66g

Question 76.
When Zinc piece is kept in CuSO4 solution the copper gets precipitated due to standard potential of Zinc is …………
(a) > copper
(b) < copper
(c) > Sulphate
(d) < Sulphate
Answer:
(b) < copper
Hint:
Standard potential of zinc < copper.

Question 77.
Which equation shows the relation between electrode potential (E) standard electrode potential (E°) and concentration of ions in solution is ………..
(a) Kohlrausch’s equation
(b) Nernst equation
(c) Ohm’s equation
(d) Faraday’s equation
Answer:
(b) Nernst equation

Question 78.
The standard electrode potential of SHE at 298K is ………
(a) 0.05 V
(b) 0.01 V
(c) 0.0 V
(d) 0.11 V
Answer:
(c) 0.0 V

Question 79.
The reaction Zn2+ + 2e → Zn has a standard potential of – 0.76 V. This means
(a) Zn cannot replace hydrogen from acids
(b) Zn is a reducing agent
(c) Zn is an oxidising agent
(d) Zn2+ is a reducing agent
Answer:
(b) Zn is a reducing agent.
Hint:
Since E0Zn2+/Zn is negative, so Zn has a greater tendency to be oxidised than hydrogen. Hence it can act as reducing agent.

Question 80.
K, Ca and Li metals may be arranged in the decreasing order of their standard electrode potentials as ……..
(a) K, Ca, Li
(b) Ca, K, Li
(c) Li, Ca, K
(d) Ca, Li, K
Answer:
(b) Ca, K, Li

Question 81.
The correct order of chemical reactivity with water according to electrochemical series ………….
(a) K > Mg > Zn > Cu
(b) Mg > Zn > Cu > K
(c) K > Zn > Mg > Cu
(d) Cu > Zn > Mg > K
Answer:
(a) K > Mg > Zn > Cu
Hint:
The standard reduction potential of K+, Mg2+, Zn2+, Cu2+ increases in this order.

Question 82.
For a spontaneous reaction, the ΔG, the equilibrium constant (K) and E°cell will be respectively
(a) ve, > 1, + ve
(b) + ve , > 1, – ve
(c) – ve, < 1, – ve (d) – ve, > 1, – ve
Answer:
(a) – ve, > 1, + ve.

Question 83.
E° values of mg2+/mg is – 2.37 V, Zn2+/ Zn is – 0.76V, and Fe2+ / Fe is – 0.44 V. Which of the following statement is correct?
(a) Zn will reduce Fe2+
(b) Zn will reduce mg2+
(c) mg oxidises Fe
(d) Zn oxidises Fe
Answer:
(a) Zn will reduce Fe2+
Hint:
E0Zn2+/Zn<E0Fe2+/Fe So Zn will reduce Fe2+. Zinc cannot reduce Mg2+ because
\(\mathbf{E}_{\mathbf{Z n}^{2+} / \mathbf{z n}}^{\circ}>\mathbf{E}_{\mathrm{Mg}^{2+} / \mathrm{Mg}}^{\circ}\) On similar reason mg and Zn cannot oxidise Fe.

Question 84.
In which cell, the free energy of a chemical reaction is directly converted into electricity?
(a) Leclanche cell
(b) Fuel cell
(c) Lead storage battery
(d) Lithium ion battery
Answer:
(b) Fuel cell

Question 85.
Which of the following has the highest electrode potential?
(a) Li
(b) Cu
(c) Au
(d) Al
Answer:
(c)Au

Question 86.
Consider the following statements.
(i) A salt bridge is used to eliminate liquid junction potential
(ii) The Gibbs free energy change ∆G is related with electro motive force (E) as ∆G = – nFE.
(iii) Nernst equation for a single electrode potential is E = E° – \(\frac { RT }{ nF }\) In \(a_{m} n^{4}\)
(iv) The efficiency of a hydrogen oxygen fuel cell is 23%.

Which of the above statement is / are not correct?
(a) (i) & (ii)
(b) (ii) & (iii)
(c) (iv) only
(d) (i) only
Answer:
(c) (iv) only

Question 87.
The specific conductance of 0.1 N KCl solution at 23°C is 0.012 Ohm-1 cm-1. The resistance of the cell containing the solution at the same temperature was found to be 55 Ohm. The cell constant will be …………
(a) 0.142 cm-1
(b) 0.66 cm-1
(c) 0.9 18 cm-1
(d) 1.12 cm-1
Answer:
(c) 0.66 cm-1
Hint:
k x \(\frac { 1 }{ R }\) x cell constant
Cell constant = k x R
= 0.012 x 55
= 0.66 cm-1

Question 88.
Which of the following reaction is used to make a fuel cell?
(a) Cd(s) + 2Ni(OH)3(s) → CdO(s) + 2Ni (OH) + H2O(1)
(b) Pb(s) + PbO2(s) + 2H2SO4(aq) → 2 PbSO4(s) + 2H2O(1)
(c) 2H2(g) + O(s) + 2H2O(1)
(d) 2Fe(s) + O2(g) + 4H+(ag) + 2Fe4(s) + 2H2O(1)
Answer:
(c) 2H2(g) + O(s) + 2H2O(1)

When lead storage battery is charged
(a) PbO2 is dissolved
(b) PbSO4 is deposited on lead electrode
(c) PbSO4 is deposited on lead electrode

Question 89.
Which colourless gas evolves when NH4CI reacts with Zinc in a dry cell battery?
(a) NH3
(b) N2
(c) H2
(d) Cl2
Answer:
(c) H2
Hint: 2NH4Cl + Zn → 2NH3 + ZnCl2 + H2

Question 91.
A cell from the following which converts electrical energy into chemical energy?
(b) Electro chemical cell
(d) Lithium – ion battery
(a) dry cell
(c) Electrolytic cell
Answer:

Question 92.
When 9.65 Coulombs of electricity is passed through a solution of silver nitrate (Atomic weight of Ag = 107.85g), the amount of silver deposited is ……………
(a) 10.8 mg
(b) 5.4 mg
(c) 16.2 mg
(d) 21.2 mg
Answer:
(a) 10.8 mg
Hint:
WAg = \(\frac{E_{A g} \times Q}{96500}\) = \(\frac{108 \times 9.65}{96500}\)
= 1.08 x 10-2

Question 93.
What weight of copper will be deposited by passing 2 Faraday’s of electricity through a cupric salt (Atomic weight of Cu = 63.5)
(a) 2.0g
(b) 3.175g
(c) 63.5g
(d) 127.0g
Answer:
(c) 63.5 g
Hint:
Cu2+ + 2e → Cu
2 Faraday’s will deposit 1g atom of Cu = 63.5 g

Question 94.
In electrolysis of a fused salt, the weight of the deposit on an electrode will not depend on ….
(a) temperature of the bath
(b) current intensity
(c) electro chemical equivalent of ions
(d) time for electrolysis.
Answer:
(a) temperature of the bath

Question 95.
The mass deposited at an electrode is directly proportional to ………..
(a) atomic weight
(b) equivalent weight
(c) molecular weight
(d) atomic number
Answer:
(b) equivalent weight

Question 96.
Which solution will show the highest resistance during the passage of current?
(a) 0.05 N NaCl
(b) 2N NaCI
(c) 0.1N NaCI
(d) 1N NaCI
Answer:
(b) 2N NaCl

Question 97.
In a galvanic cell, the electrons flow from
(a) anode to cathode through the solution
(b) cathode to anode through the solution
(c) anode to cathode through the external circuit
(d) cathode to anode through the external circuit
Answer:
(c) anode to cathode through the external circuit

Question 98.
Rusting of iron is catalysed by which of the following?
(a) Fe
(b) O2
(c) Zn
(d) H
Answer:
(d) H

Question 99.
The conductivity of strong electrolyte is ………..
(a) increase on dilution slightly
(b) decrease on dilution
(c) does not change with dilution
(d) depend upon density of electrolyte itself
Answer:
(a) increase on dilutions lightly

Question 100.
Which one is not a conductor of electricity?
(a) NaCl(aqueous)
(b) NaCl(solid)
(c) NaCl(molten)
(d) Ag(metal)
Answer:
(b) NaCl(solid)
Hint:
In solid state, NaCl does not dissociate into ions so it does not conduct electricity.

Question 101.
The molar conductivity is maximum for the solution of concentration
(a) 0.00 1 m
(b) 0.005 m
(c) 0.002 m
(d) 0.004 m
Answer:
(a) 0.001 m
Hint:
molar conductance α \(\frac{1}{\text { molarity }}\)

Question 102.
Resistance of 0.2 m solution of an electrolyte is 50 Ohm-1. The specific conductance of the solution is 1.3 Sm-1. If resistance of 0.4 m solution of the same electrolyte is 260 Ohm-1, its molar conductivity is ……..
(a) 62.5 Sm2 mol-1
(b) 6250 Sm2 mol-1
(c) 6.25 x 10-4 Sm2 mol-1
(d) 625 x 10-4 Sm2 mol-1
Answer:
(c) 6.25 x 10-4 Sm2 mol-1

Question 103.
Saturated solution of KCI (or) Na2SO4 is used to make salt bridge because
(a) velocity of K+ is greater than that of Cl
(b) velocity of Cl is greater than that of K+
(c) velocity of both K+ and Cl-1 are nearly the same
(d) KCI is highly soluble in water.
Answer:
(c) velocity of both K+ and Cl are nearly the same

Question 104.
Which of the following electrolytic solutions has the least specific conductance?
(a) 0.02 N
(b) 0.2 N
(c) 2 N
(d) 0.002 N
Answer:
(d) 0.002 N

Question 105.
An increase in equivalent conductance of a strong electrolyte with dilution is mainly due to ……….
(a) increase in both the number of ions and ionic mobility of ions
(b) increase in number of ions
(c) increase in ionic mobility of ions
(d) 100% ionization of electrolyte at normal dilution
Answer:
(c) increase in ionic mobility of ions

Question 106.
Li occupies higher position in the electrochcmical series of metals as compared to Cu, since
(a) the standard reduction potential of Li+/Li is lower than that of Cu2+/Cu
(b) the standard reduction potential of Cu2+/Cu is lower than that of Li+/Li
(c) the standard oxidation potential of Li/Li+ is lower than that of Cu/Cu2+
(d) Li is smaller in size as compared to Cu.
Answer:
(a) the standard reduction potential of Li+/Li is lower than that of Cu2+/Cu

Question 107.
The one which decreases with dilution is …………
(a) conductance
(b) specific conductance
(c) equivalent conductance
(d) molar conductance
Answer:
(b) specific conductance

Question 108.
Corrosion of iron is essentially an electrochemical phenomenon where the cell reactions are …………..
(a) Fe is oxidised to Fe2+ and dissolved oxygen in water is reduced to OH
(b) Fe is oxidised to Fe2+ and H2O is reduced to O22-
(c) Fe is oxidised to Fe2+ and H2O is reduced to O2
(d) Fe is oxidised to Fe2+ and H2O is reduced to O2
Answer:
(a) Fe is oxidised to Fe2+ and dissolved oxygen in water is reduced to OH-2

Question 109.
A button cell used in watches functions as following.
Zn(s) + Ag2O(s) + H2O(1) → 2 Ag(s) + Zn2+(aq)+ 2OHsup>-(aq).
If half cell potentials are Zn2+(aq) + 2e → Zn(s)
E° = – O.76V
Ag2O(s) + H2O(1) +2e 2Ag(s) + 2OH(aq)E0 = 0.34V
The cell potential will be ………..
(a) 1.10V
(b) 0.42V
(c) 0.84V
(d) 1.34V
Answer:
(a) 1.10V
Hint:
Cell potential = Ecathode – Eanode
= 0.34 – (- 0.76)
= 0.34 + 0.76
= 1.10V

Question 110.
Among the following cells Leclanche cell
(I) Nickel – cadmium cell
(II) Lead storage battery
(III) and Mercury Cell
(IV) primary cells are
(a) I & II
(b) I & III
(c) II & III
(d) I & IV
Answer:
(d) I & IV

II. Fill in the blanks.

  1. ……… is defined as the resistance of an electrolyte confined between two electrodes having unit cross sectional area and separated by a unit distance
  2. The reciprocal of the specific resistance is called the and represented by the symbol ………
  3. The SI unit of specific conductance is ………
  4. The relation between equivalent conductance and the specific conductance is given as ………
  5. Conductivity increases with the ……… in viscosity.
  6. m values of the weak electrolytes can be determined using ………
  7. ……… is a device in which a spontaneous chemical reaction generates an electric current.
  8. ……… is a device that converts electrical energy into chemical energy.
  9. The salt bridge contains a agar-agar gel mixed with an inert electrolyte such as ………
  10. The SI unit of cell potential is ………
  11. The reference electrode SHE has emf of exactly ……… volt
  12. The value of charge of one electron is equal to ………
  13. For a spontaneous cell reaction, the should be ………
  14. ……… is a process in which electrical energy is used to cause a non-spontaneous chemical reaction.
  15. The negative E° values shows that the reactions are ………
  16. ……… is defined as the amount of a substance deposited or liberated at the electrode by a charge of 1 Coulomb.
  17. ……… batteries are used in cell phones.
  18. ……… cell is used in pacemakers, electronic watches and cameras.
  19. ………battery is used in automobiles.
  20. Rusting of iron is an ……… process.

Answer:

  1. Specific resistance (or) Resistivity
  2. Specific conductance, Kappa(k)
  3. Sm-1
  4. Λ = \(\frac{\kappa \times 10^{-3}}{N}\)
  5. decrease
  6. Kohlraush’s law
  7. Galvanic (or) Voltaic cell
  8. Electrolytic cell
  9. KCl (or) Na2SO4
  10. Volt (V)
  11. zero
  12. 1.6 x 10-19C
  13. negative
  14. Electrolysis
  15. non – spontaneous
  16. electro chemical equivalent
  17. Li-ion
  18. Mercury button
  19. Lead storage
  20. electro chemical

III. Match the following

Question 1.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-37
Answer:
i. c d a b

Question 2.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-38
Answer:
ii. c a d b

Question 3.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-39
Answer:
iii. d c a b

Question 4.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-40
Answer:
iv. c a d b

Question 5.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-41
Answer:
i. b c d a

Question 6.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-42
Answer:
i. c a d b

IV. Assertion and reasons.

Question 1.
Assertion(A): If the temperature of the electrolytic solution increases, conductance also increases.
Reason (R): Increase in temperature increases the kinetic energy of the ions and decreases the attractive force between the oppositely charged ions and hence conductivity increases.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are wrong
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 2.
Assertion(A): Molar conductance of a solution increases with increase in dilution.
Reason (R): For a strong electrolyte, inter ionic forces of attraction decreases with dilution and so conductivity increases. For a weak electrolyte, degree of dissociation increases with dilution and conductivity increases.
(a) Both A and R are correct and R is the correct explanation of A .
(b) A and R are wrong
(c) A is correct but R is not the explanation of A
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 3.
Assertion(A): AC current is used in wheatstone bridge arrangement to measure conductivity of ionic solution.
Reason (R): If DC current is used in wheatstone bridge arrangement, it will lead to electrolys is of the solution taken in the cell. So AC current is used to prevent electrolysis.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are wrong
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 4.
Assertion(A): Strong electrolytes have low molar conductivity at high concentration.
Reason (R): For a strong electrolyte, at high concentration, the number of constituent ions of the electrolyte is high and hence the attractive force between the oppositely charged ions is also high
(a) Both A and R are correct and R is the correct explanation of A
(b) A is correct but R is wrong
(c) A is wrong but R is correct
(d) Both A and R are wrong
Answer:
(a) Both A and R are correct and R is the correct explanation of A

Question 5.
Assertion(A): In Daniel cell, the salt bridge contains an agar-agar gel mixed with an inert electrolyte KCl (or) Na2SO4.
Reason (R): The ions of inert electrolyte do not react with other ions present in half cells and they are not either oxidised or reduced at electrodes.
(a) Both A and R are correct
(b) Both A and R are wrong
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct

Question 6.
Assertion(A): Current stops flowing when Ecell = 0
Reason (R): At Ecell = 0, Equilibrium of the cell reaction is attained.
(a) Both A and R are correct
(b) Both A and R are wrong
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct

Question 7.
Assertion(A): Copper Sulphate can be stored in a Zinc vessel.
Reason (R): Zinc is less reactive than Copper.
(a) Both A and R are correct
(b) Both A and R are wrong
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct

Question 7.
Assertion(A): Copper Sulphate can be stored in a Zinc vessel.
Reason (R): Zinc is less reactive than Copper.
(a) Both A and R are correct
(b) Both A and R are wrong
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(b) Both A and R are wrong

Question 8.
Assertion(A): As a lead storage battery gets discharged. density of electrolyte present in it decreases.
Reason (R): Lead and Lead dioxide both react with sulphuric acid to form lead sulphate.
(a) Both A and R are correct
(b) A is correct but R is wrong
(c) A is wrong but R is correct
(d) Both A and R are wrong.
Answer:
(a) Both A and R are correct

Question 9.
Assertion(A): The cell potential of mercury cell is 1.35V which remains constant.
Reason (R): In mercury cell, the electrolyte is a paste of KOH and ZnO.
(a) Both A and R are correct, but R is not the correct explanation of A
(b) Both A and R are correct, but R is the correct explanation of A
(c) A is wrong but R is correct
(d) A is correct but R is wrong
Answer:
(a) Both A and R are correct, but R is not the correct explanation of A

Question 10.
Assertion(A): If an iron rod is dipped in CuSO4 solution, then blue colour of the solution turns red.
Reason (R): Iron is more reactive than copper and so iron displaces copper from CuSO4 solution.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are wrong
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A

V. Find the odd one out and give the reasons.

Question 1.
(a) I α V
(b) I = \(\frac { V }{ R }\)
(c) V = IR
(d) R = \(\frac { I }{ V }\)
Answer:
(d) R is the odd one, and other three represents Ohm’s law

Question 2.
(a) m = Zit
(b) Z = \(\frac { m }{ It }\)
(c) m α It
(c) \(\frac{\mathrm{m}_{1}}{\mathrm{Z}_{1}}$\) = \($\frac{\mathrm{m}_{2}}{\mathrm{Z}_{2}}\)
Answer:
(d) \(\frac{\mathrm{m}_{1}}{\mathrm{Z}_{1}}$\) = \($\frac{\mathrm{m}_{2}}{\mathrm{Z}_{2}}\) = is the odd one, all the others are Faraday’s I law but (ci) is Faraday’s ¡I law

Question 3.
(a) Pacemaker
(b) electronic watches
(c) trains
(d) cameras
Answer:
(c) train, Lead storage battery is used in trains, but in all others mercury button cell is used up.

Question 4.
(a) Automobiles
(b) Pacemaker
(c) Train
(d) Inverters
Answer:
(b) Pacemaker. In pacemaker mercury button cell is used whereas in other three, lead storage battery is used up.

Question 5.
(a) Cellular phone
(b) Laptop
(c) Digital Camera
(d) Electronic watch
Answer:
(d) Electronic watch. ¡n this mercury button cell is used whereas in others Li-ion battery is used up.

Samacheer Kalvi 12th Chemistry Electro Chemistry 2 Mark Questions and Answers

VI. Answer the following.

Question 1.
State Ohm’s law.
Answer:
At a constant temperature, the current flowing through the cell (I) is directly proportional to the voltage across the cell (V).
I α V(or) I = \(\frac { V }{ R }\)
V = IR

Question 2.
Define Resistivity. Give its unit.
p (rho) is called the specific resistance (or) resistivity and it is defined as the resistance of an electrolyte confined between two electrodes having unit cross sectional area and are separated by a unit distance. Unit of resistivity is Ohm metre (Ω m)

Question 3.
Define conductance and give its unit.
Answer:
The reciprocal of the resistance \((\frac { 1 }{ 2 })\) is known as the conductance of an electrolytic solution.
The SI unit of conductance is Ohm-1 (or) Siemen (S)

Question 4.
Define specific conductance. Give its SI unit.
Answer:
The specific conductance is defined as the conductance of a cube of an electrolytic solution of unit dimensions. The SI unit of specific
k = C . \(\frac { l }{ A }\)
conductance is Sm-1

Question 5.
What Is meant by resistance? Give its unit.
Answer:
Resistance is the opposition that a cell offers to the flow of electric current through it.
R α \(\frac { l }{ A }\)
The SI unit of R = Ohm (Ω)

Question 6.
What is molar conductance? Give its SI unit.
Answer:
The conductance of a conductivity cell in which the electrodes are separated by 1m and having V m3 of electrolytic solution that contains 1 moIe of an electrolyte is known as molar conductance.
Λm = k x V
The SI unit of Λm = S m2 mol-1

Question 7.
Define equivalent conductance. Give its SI unit.
Answer:
Equivalent conductance is defined as the conductance of ‘V’ m3 of electrolytic solution containing one gram equivalent of electrolyte in a conductivity cell in which the electrodes are one metre apart.
Λ = \(\frac{\kappa \times 10^{-3}}{N}\)
The SI unit of A = S m2 gm equivalent’

Question 8.
What are electro chemical cells? Mention its types.
Answer:
Electro chemical cell is a device which inter converts chemical energy into electrical energy and vice versa. It consists of two separate electrodes which are in contact with an electrolyte solution. Electro chemical cells are classified into two types.

  1. Galvanic cell and
  2. Electrolytic cell.

Question 9.
Distinguish between galvanic cell and electrolytic cell.
Answer:
Galvanic Cell

  1. It is a device in which a spontaneous chemical reaction generates an electric current.
  2. It converts chemical energy into electrical energy. It is commonly known as Battery.
  3. e.g., Daniel cell, Dry cell.
  4. A salt bridge is used in this.

Electrolytic cell

  1. It is a device in which an electric current from an external source drives a non spontaneous reaction
  2. It converts electrical energy into chemical energy.
  3. e.g., Electrolysis of molten NaCI.
  4. Na salt bridge is used.

Question 10.
What is meant by Faraday? How is it calculated?
Answer:
One Faraday is defined as the charge of one mole of electron.
Charge of one electron = 1.6 x 10-19C
Charge of 1 mole of electrons = 6.023 x 1023 x 1.602 x 10-19C
= 6.023 x 1023 x 1.602 x 10-19C
= 96488 C
i.e., IF ≃ 965O0C

Question 11.
Define corrosion. Give one example.
Answer:
The redox process which causes the deterioration of metal is called corrosion. Rusting of iron is an example of corrosion. It is an electro chemical process.

Question 12.
Can you store copper sulphate solution in a zinc pot?
Answer:
Zinc is more reactive than copper. Hence, it displaces copper from copper sulphate solution as follows
Zn(s) + CuSO4(aq) → ZnSO4(aq) + Cu (s) So, we cannot store copper sulphate solution in a zinc pot.

Question 13.
Why does the conductivity of a solution decrease with dilution?
Answer:
Conductivity of a solution is the conductance of ions present in a unit volume of solution. On dilution the number of ions per unit volume decreases. Hence, the conductivity decrease.

Question 14.
Suggest a way to determine 10m value of water.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-67
We find out
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-68
Then
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-69

Question 15.
Write the chemistry of recharging the lead storage battery, highlighting all the materials that are involved during recharging? .
A lead storage battery consists of anode made up of lead, cathode made up of grid of lead packed with lead dioxide (PbO2) and 38% solution of sulphuric acid is used as an electrolyte. When the battery is in use, the following reaction take place:
Anode: Pb(s) + SO42-(aq) → PbSO4(s) + 2e
Cathode: PbO2(s) + SO42-(aq) + 4H+(aq) + 2e → 2PbSO4(s) + 2H2O(1)
On charging the battery, the reverse reaction takes place, i.e. PbSO4 deposited on the electrode is converted back into Pb and PbO2 and H2SO4 regenerated.

Question 16.
What is meant by cell constant?
Answer:
Cell constant is the ratio of the distance between the electrodes (l) and the area of cross-section (A). It is denoted by 1. Its unit is cm-1. Its SI unit is m-1.

Question 17.
State two advantages of H2 – O2 fuel cell over ordinary cells.
Answer:

  1. It is highly efficient.
  2. It is pollution free

Question 18.
Why Om for CH3COOH cannot be determined experimentally?
Answer:
Molar conductivity of weak electrolytes keeps on increasing with dilution and does not become constant even at very large dilution.

Question 19.
Which will have greater molar conductivity and why?
Answer:
Sol. (A) 1 mol KCI dissolved in 200 cc of the solution.
Sol. (B) 1 mol KCI dissolved in 500 cc of the solution.
Sol. (B) will have greater molar conductivity because
λm = k x V
with dilution K decreases but V increases, so that product will increase more.

Question 20.
Raju and his father were going in a boat in the river. Raju’s father was going to throw away the cell used in watches and hearing aids into the water. Raju prevented him doing so.

  1. As a student of chemistry, why would you advise Raju’s father not to throw the cell in the water body?
  2. What is the value associated with the above decision?

Answer:

  1. The watch cells are made up of mercury. This mercury will pollute the water. Water contaminated with mercury leads to accumulation of mercury in the body of fishes and other aquatic life.
  2. It helps in keeping the environment safe from pollution due to mercury.

Samacheer Kalvi 12th Chemistry Electro Chemistry 3 Mark Questions And Questions

VII.Answer the following questions.

Question 1.
Explain about conductivity cell with an example.
Answer:
1. Sodium chloride (or) potassium chloride is dissolved in a solvent like water, the electrolyte is completely dissociated to give its constituent ions (cations and anions).

2. When an electric field is applied to such an electrolytic solution, the ions present in the solution carry charge from one electrode to another. PLattnium electrode and thereby they conduct electricity. electrode

3. The conductivity of the electrolytic solution is measured using a conductivity cell, solution
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-43

Question 2.
Explain about the factors affecting electrolytic conductance. Conductivily Cell
Answer:

  1. If the interionic attraction between the oppositely charged ions ofsolute increases, the conductance will decrease.
  2. Solvent of high dielectric constant show high conductance in solution.
  3. Conductance is inversely proportional to the viscosity of the medium. i.e., conductivity increases with the decrease in viscosity.
  4. If the temperature of the electrolytic solution increases, conductance also increases.
  5. Molar conductance of a solution increases with increase in dilution. This is because, for a strong electrolyte, inter ionic force of attraction decrease with dilution.
  6. For a weak electrolyte, degree of dissociation increases with dilution.

Question 3.
Explain about the variation of molar conductivity with concentration by Kohiraush studies?
Answer:
Kohiraush observed that, increase of molar conductance of an electrolytic solution with the increase in dilution. He deduced the following empirical relationship between the molar conductance (Λm) and concentration of the
Λm = Λ0m – k\(\sqrt { c }\)
For strong electrolytes such as KCl, NaCl the plot ΛmVs\(\sqrt { c }\), gives a straight line. It is also observed that the plot is not a linear one for weak electrolyte.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-44

Question 4.
For strong electrolytes the molar conductivity increases on dilution and reaches a maximum value at infinite dilution. Justify this statement.
Answer:
For a strong electrolyte, at high concentration, the number of constituent ions of the electrolyte in a given volume is high and hence the attractive force between the oppositely charged ions is also high. The ions also experienced a viscous drag due to greater solvation. These factors attribute for the low molar conductivity at high concentration.

When the dilution increases, the ions are far apart and the attractive forces decreases. At infinite dilution, the ions are so far apart, the interaction between them becomes insignificant and hence the molar conductivity increases and reaches a maximum value at infinite dilution.

Question 5.
For weak electrolyte, sudden increase In molar conductance with dilution. Prove this statement.
Answer:
For a weak electrolyte, at high concentration the plot is almost parallel to concentration axis with slight increase in conductivity as the dilution increases. When the concentration approaches zero, there is a sudden increase in the molar conductance and the curve is almost parallel to Am axis. This is due to the fact that the dissociation of the weak electrolyte increases with the increase in dilution (Ostwald’s dilution law).

Question 6.
Explain about Debye-Huckel and Onsagar equation.
Answer:
The influence of ion-ion interactions on the conductivity of strong electrolytes was studied by Debye and Huckel.
They considered that each ion is surrounded by an ionic atmosphere of opposite sign, and derived an expression relating the molar conductance of strong electrolytes with the concentration by It was further developed by Onsagar. For a uni – univalent electrolyte the Debye Huckel and Onsagar equation is given below.
Λm = Λ°m (A + B Λ°m) \(\sqrt { c }\)
Where A and B are constants which depend only in the nature of the solvent and temperature.

Question 7.
What are the values of A and B in Debye Huckel and Onsagar equation?
Answer:
Debye Huckel and Onsagar equation is
Λm = Λ°m (A + B Λ°m) \(\sqrt { c }\)
Where
\(\mathrm{A}=\frac{82.4}{\sqrt{\mathrm{DT}} \mathrm{n}}\)
\(B=\frac{8.20 \times 10^{5}}{3 \sqrt{D T}}\)
D = Dielectric constant of the medium
η = Viscosity of the medium
T = Temperature in Kelvin

Question 8.
How will you calculate degree of dissociation of weak electrolytes and dissociation constant using Kohlrausch’s law?
Answer:
1. The degree of dissociation of weak electrolyte can be calculated from the molar conductivity at a given concentration and the molar conductivity in infinite dilution using the formula

2. According to Ostwald’s dilution law Ka = \(\frac{\alpha^{2} C}{1-\alpha}\)
Substituting a value in the above equation
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-45

Question 9.
How would you calculate the solubility of sparingly soluble salt using Kohlrausch’s law?
Answer:
1. Substances like AgCl, PbSO4 are sparingly soluble in water. The solubility product can be determined using conductivity experiments.

2. Let us consider AgCl as an example
AgCI(s) → Ag+ + Cl
Ksp = [Ag+] [Cl]

3. Let the concentration of [Ag+] be ‘C’ mol L-1.
If [Ag+] = C, then [Cl] is also equal to C mol L-1.
Ksp = C.C
Ksp = C2.

4. The relationship between molar conductance and equivalent conductance is
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-46
Substitute the concentration value in the relation Ksp = C2
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-47

Question 10.
What is the relationship between molar mass and electro chemical equivalent. Derive the equation.
Answer:
1. Consider the following general electro chemical redox reaction
Mn+(aq) + ne → M(s)

2. We can infer from the above equation that ‘n’ moles of electrons are required to precipitate

3. The quantity of charge required to precipitate 1 mole of Mn+ = Charge of ‘n’ moles of electrons = nF

4. In other words, the mass of the substance deposited by one coulomb of charge. Molar mass (M)
Electro chemical equivalent Mn+ = \(\frac{\text { Molar mass }(\mathrm{M})}{\mathrm{n}(96500)}\)
(or)
Z = \(\frac{\text { Equivalent mass }}{96500}\)

Question 11.
What is meant by standard reduction potential? What is its application?
Answer:
1. The standard reduction potential (E°) is a measure of the oxidising tendency of the species.
2. The greater the E° value means greater is the tendency shown by the species to accept electrons and undergo reduction.
3. So higher the E° values, lesser is the tendency to undergo corrosion.

Question 12.
What is meant by Electro chemical series? Mention the top most and the least placed element in that series.
Answer:
1. The standard aqueous electrode potential at 298 K for various metal-metal ion electrodes are arranged in the decreasing order of their standard reduction potential values is known as electro chemical series.

2. The strongest reducing agent is Li which has E° value as – 3.05 and it is in bottom of the series.

3. The strongest oxidising agent is F which has E° value as + 2.87 is the first element in that series.

Question 13.
Calculate the emf of the cell in which the following reaction takes place
Ni(s) + 2Ag+(0.002 M) —‘ Ni2+(0.160 M) + 2 Ag(s)
Given that E°cell = 1.05 V
Answer:
Applying Nernst equation to the given cell reaction:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-48
= 1.05 – 0.14 V = 0.91 V

Question 14.
If a current of 0.5 ampere flows through a metallic wire for 2 hours, then how many electrons would flow through the wire?
Answer:
Q (coulomb) = 1 (ampere) x t(sec)
= 0.5 ampere x 2 x 60 x 60 = 3600C
A flow of IF, i.e., 96500 C is equivalent to the flow of 1 mole of electrons
i.e., 6.023 x 1023electrons
3600 C is equivalent to flow of electrons
= \(\frac{6.02 \times 10^{23}}{96500}\) x 3600 2.246 x 1022 electrons,

Question 15.
What are fuel cells? Write the electrode reactions of a fuel cell which uses the reaction of hydrogen with oxygen?
Answer:
A fuel cell is similar to a galvanic cell, it generates electricity directly by the electrochemical conversion of gaseous or liquid fuels fed into the cell as required.
At anode: H2(g) + 2OH(aq) → 2H2O(l) + 2e
At cathode: O2(g) + 2H2O(1) + 4e → 4OH(aq)
Overall reaction : 2H2(g) + O2(g) → 2H2O(l)

Question 16.
Write the cell reaction which occur ¡n the lead storage battery

  1. When the battery is in use,
  2. When the battery is charging.

Answer:
1. Pb(s) + PbO2(s) + 2H2SO4(aq) → 2PbSO4(s) + 2H2O(1)
At anode: Pb(s) + SO2-4 → PbSO4(s) + 2e
At cathod: PbO4(s) + SO2-4(aq) + 4H+(aq) + 2e → PbSO4(s) + 2H2O(1)

2. 2PbSO4(s) + 2H2O(s) → PbSO4(s) + 2H2SO4(aq)

Question 17.
Describe the composition of anode and cathode in a mercury cell. Write the electrode reactions for this cell.
Answer:
Mercury cell: It consists of zinc mercury amalgam as anode, a paste of HgO and Carbon black is used as cathode. The electrolyte is a paste of KOll and ZnO.
At anode: Zn (amalgam) + 2OH → ZnO(s) + H2O(l) + 2e
At cathode: HgO(s) + H2O + 2e → Hg(1) + 2OH
The net reaction : Zn (amalgam) + HgO(s) → ZnO(s) + Hg(l)

Question 18.
How much copper is deposited on the cathode of an electrolytic cell If a current of 5 ampere is passed through a solution of copper sulphate for 45 minutes?
Answer:
[Molar mass of Cu = 63.5 g mol-1, IF = 96,500 C mol-1]
Cu2+(aq) + 2e → Cu(s)
m = Z xI x t
= \(\frac{63.5}{2 \times 96500}\) x 5amp x 45 x 60 = \(\frac { 857250 }{ 193000 }\) = 4.44g

Question 19.
How much time would it take in minutes to deposit 1.18 g of metallic copper on a metal object when a current of 2.0 A is passed through the electrolytic cell containing Cu2+ ions?
Answer:
[Molar mass of Cu = 63.5 g mol-1, IF = 96,500 C mol-1]
m = Z x I x t
1.18 = \(\frac{63.5}{2 \times 96500}\)
t = \(\frac{1.18 \times 2 \times 96500}{2 \times 63.5}\)
= 1793.23 sec
= \(\frac { 1793.23 }{ 60 }\) = 29.88 min

Question 20.
What is a salt bridge? What is it used for?
Answer:
A salt bridge is a U – shaped tube containing concentrated solution of an inert electrolyte like KCl, KNO3, K2SO4, etc., or a solidified solution of an electrolyte such as agar-agar and gelatine. It is used,

  1. To complete the electrical circuit by allowing ions to flow from one solution to the other without mixing the two solutions.
  2. To maintain the electrical neutrality of the solutions in the two half cells.

Question 21.
Calculate emf of the following cell of 25°C.
Answer:
Fe | Fe2+(0.001M) || H+(0.01M) | H2(g) (1 bar) pt
E0(Fe2+/Fe) = – 0.44V
E0(H+/H2) = 0.00V
Cell reaction
Fe + 2H+ Fe2+ + H2
E0cell = E0cathode – E0anode
E0cell = 0.44 – \(\frac{0.0591}{2}\) 10 g \(\frac{\left[10^{-3}\right]}{\left[10^{-2}\right]^{2}}\)
= 0.44 – \(\frac{0.0591}{2}\) 10g 10
= 0.44 – \(\frac{0.0591}{2}\)
E0cell = 0.4105V

Question 22.
What is corrosion? CO2 is always present in natural water. Explain its effect (increases, stops or no effect) on rusting of Fe.
Answer:
Corrosion is a process of slowly eating away of the metal due to the attack of atmospheric gases on thc surface of metal resulting into the formation of compounds such as oxides, suiphides, carbonates, suiphates, etc.

Factors affecting corrosion are:

  1. Reactivity of metal
  2. Presence of impurities
  3. Presence of air and moisture
  4. Strains in metals
  5. Presence of electrolytes

CO2 increases the rusting of iron because greater the number of W ions, faster the rusting will take place.

Samacheer Kalvi 12th Chemistry Electro Chemistry 5 Marks Question

VIII.Answer the following questions.

Question 1.
How would you measure the conductivity of ionic solutions?
Answer:
1. The conductivity of an electrolytic solution is determined by using a wheatstone bridge arrangement in which one resistance is replaced by a conductivity cell filled with the electrolytic solution of unknown conductivity.

2. In the measurement of specific resistance of a metallic wire, a DC power supply is used. Here AC is used for this measurement to prevent electrolysis. Because DC current through the conductivity cell leads to the electrolysis of the solution taken in the cell.

3. A wheatstone bridge is constituted using known resistances P,Q, a variable resistance S and conductivity cell. An AC source (550 Hz to 5 KHz) is connected between the junctions A and C. A suitable detector is connected between the junctions B and D.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-49

4. The variable resistance S is adjusted until the bridge is balanced and in this canditions, there is no current flow through the detector.

5. Under balanced condition
P/Q = R/S
R = P/Q x S ………..(1)
The resistance of the electrolytic solution (R) is calculated from the known resistance values P, Q and the measured S value using the equation (1).

6. Specific conductance (or) conductivity of an electrolyte can be calculated from the resistance value (R) using the following expression

7. The value of cell constant is usually provided by the cell manufacturer. Alternatively the cell constant may be determined using KCI solution whose concentration and specific conductance are known.

Question 2.
Explain about SHE (Standard Hydrogen Electrode).
Answer:
1. It is impossible to measure the emf of a single electrode, but we can H2 out H2 measure the potential difference between two electrodes (Ecell) using a voltmeter.

2. To calculate the emf of a single electrode, we need a reference electrode whose emf is known. For that purpose, Standard Hydrogen
Electrode (SHE) is used as the reference electrode.

3. SHE has been assigned an orbitary emf of exactly zero volt.

4. It consists of platinum electrode in contact with 1M HC1 solution and 1 atm hydrogen gas.

5. The hydrogen gas bubbled through the solution at 25°C. SHE can act as cathode as well as an anode.

6. The Half cell reactions are given below:
If SHE is used as a cathode, the reduction reaction is
2H2 + 2e + H2(g,1 atm) E°= 0 volt
If SHE is used as an anode, the oxidation reaction is
H2(g, 1 atm) 2H+( aq, 1M) + 2e E° = 0 volt.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-50

Question 3.
How would you determine the reduction potential of Zn/Zn2+(aq)? (or) How will you calculate the reduction potential of Half cell?
Answer:
1. Consider the zinc electrode dipped in zinc sulphate solution using SHE
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-51

2. Step 1:
The following galvanic cell is constructed using SHE
Zn(s) | Zn2+(aq.1M) | H2(g.1atm) | Pt(s)

3. Step 2:
The emf of the above galvanic cell is measured using a voltmeter. In this case the measured emf of the above galvanic cell is 0.76 V

4. Calculation:
We know that.
cell = (E°ox)zn|zn2+ + (E°red)SHE
cell = 0.76 + 0V
= 0.76 V
This oxidation potential corresponds to the below mentioned half cell reaction which takes place at the cathode
Zn → Zn2+ + 2e (oxidation)
(y) The emf of the reverse reaction will give the reduction potential
Zn2+ + 2e → Zn
(E°red)zn2+|zn = – 0.76V

Question 4.
Derive the relationship between Gibb’s free energy and maximum work obtained from galvanic cell and equilibrium constant.
Answer:
1. In a galvanic cell, chemical energy is converted into electrical energy. The electrical energy produced by the cell is equal to the product of the total charge of the electrons and emf of the cell which drives these electrons between the electrodes.

2. If ‘n’ is the number of moles of electrons exchanged between the oxidising and reducing
agent in the overall cell reaction, then the electrical energy produced by the cell is given
as below.
Electrical energy = change of ‘n’ moles of electrons x Ecell ……………..(1)
Charge of I mole of electrons = one Faraday = 1F
Charge of n moles of electrons = nF ……………..(2)

3. Electrical energy = nFEcell …………….(3)
This energy is used to do electric work. Therefore the maximum work that can be obtained from a galvanic cell is
Here the – ve sign is introduced to indicate that work is done by the system on the surroundings.

4. Second law of thermodynamics states that the maximum work done by the system is equal to the change in Gibbs free energy of the system
Wmax = ΔG …………..(5)

5. ΔG = – nFEcell (6)
For a spontaneous cell reactions, the AG should be negative. The above expression indicates that Ecell should be positive to get a negative AG value.

6. When all the cell components are in their standard state, the equation (6) becomes
ΔG° = – nFE°cell …………….(7)

7. The standard free energy change is related to the equilibrium constant as per the following equation.
ΔG° = – RT In Keq …………..(8)
Comparing equations (7) and (8)
nFE°cell = RT In Keq …………..(9)
nFE°cell = \(\frac { 2.303RT }{ nF }\) log Keq ………………(10)

Question 5.
Describe about the working principle of Leclanche cell.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-52
1. Leclanche cell:
Anode: Zinc container
Cathode: Graphite rod in contact with MnO2
Electrolyte: Ammonium chloride and Zinc chloride in water.
emf of the cell = 1.5 V

2. Cell reaction:
Oxidation at anode
Zn(s) → Zn2+(aq) + 2e ……………(1)
Reduction at cathode
2NH+4 (aq) + 2e → 2NH3(aq) + H2(aq)

3. The hydrogen gas is oxidised to water by MnO2
H2(g)+ 2MnO2(s) → Mn2O3(s) + H2O(1) ……(3)
Adding equations 1,2,3 the overall redox reaction
Zn(s) + 2NH+4(aq) + 2MnO2(s) → Zn2+(aq) + Mn2O3(s) + H2O(1) + 2NH3 …………….(4)

4. The ammonia produced at the cathode combines with Zn2+ to form a complex ion [Zn (NH3)4]2+(aq). As the reaction proceeds, the concentration of NH4+ will decrease and the aqueous NH3 will increase which lead to the decrease in the emf of the cell.

Question 6.
Explain about the construction and uses of mercury button cell.
Answer:
1. Mercury button cell:
Anode: Zinc Amalgamated with mercury
Cathode: HgO mixed with graphite
Electrolyte: Paste of KOH and ZnO.

2. Oxidation occurs at anode:
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-70

3. Reduction occurs at cathode
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-71
Hg(s) + 2OH(aq)
Overall reaction is
Zn(s) + HgO(s) → ZnO(s) + Hg(1)

4. Cell emf: about 1.35 V
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-53

5. Uses:
It has higher capacity and longer life. It is used in pacemakers, electronic watches, cameras.

Question 7.
Describe about lead storage battery construction and its uses.
Answer:
Lead storage battery:
1. Anode – Spongy lead
Cathode – Lead plate bearing PbO2
Electrolyte – 38% by mass of H2SO4 with density 1.2 g/ml

2. Oxidation occurs at the anode
Pb(s) → Pb2+(aq) + 2e ………..(1)
The Pb2+ ions combine with SO42- to form PbSO4 precipitate
Pb2+(aq) + SO42- → PbSO4(s)         …………(2)

3. Reduction occurs at the cathode
PbO2(s) + 4H+(aq) + 2e → + 2H2O(1)     ……….(3)
The Pb2+ ions also combines with SO42- ions to form sulphuric acid to form PbSO4 Precipitate
Pb2+(aq) + SO2-2+ → PbSO         ………….(4)

4. The overall reaction is,
(1) + (2) + (3) + (4)
Pb(s) + pbO2(s) + 4H+(s) + 2SO2-4(s) → 2PbSO4(s) + 2H2O(1)

5. The emf of a single cell is about 2V. Usually six such cells are combined in series to produce 12 volts.

6. The emf of the cell depends on the concentration of H2SO4. As the cell reaction uses SO42- ions, the concentration H2SO4 decreases. When the cell potential falls to about 1.8V, the cell has to be recharged.

7. Recharge of the cell – During recharge process, the role of anode and cathode is reversed and H2SO4 is regenerated. Oxidation occurs at cathode (now anode)
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-54
Reduction occurs at anode (now cathode)
PbSO4(s) + 2e → Pb(s) + SO2-4(sq)
Overall reaction
2 pbSO4(s) + 2H2O(1) → pb(s) + pbO2(s) + 4H+(aq) + 2SO2-4(aq)
The above reaction is exactly the reverse of redox reaction which takes place while discharging.

8. Uses: Lead storage battery is used in automobiles, trains, inverters.

Question 8.
Describe about lithium-ion battery and its uses.
Answer:
1. Lithium-ion battery
Anode – Porous graphite
Cathode – Transition metal oxide as CoO2
Electrolyte – Lithium salt in an organic solvent

2. At the anode oxidation occurs
Li(s) → Li+(aq) + e
At the cathode reduction Occurs.
Li+ + CoO2(s) + e → Li CoO2(s)

3. Overall reactions
Li(s) + CoO2 → Li CoO2(s)

4. Both electrodes allow Li ions to move in and out of their structures. During discharge the Li ions produced at the anode moves towards cathode through the non-aquaeous electrolyte.

5. When a potential greater than the emf produced by the cell is applied across the electrode, the cell reaction is reversed and now the Li+ ions move from cathode to anode where they become embedded on the porous electrode. This is known as intercalation.

6. Uses: This Li-ion battery is used in cellular phones, Laptop computer and digital camera.

Question 9.
What is corrosion? Explain about the electrochemical mechanism of corrosion.
Answer:
1. The metal is oxidised by oxygen in the presence of moisture. The redox process which causes the deterioration of metal is called corrosion.

2. Corrosion of iron is known as Rusting and it is an electrochemical process.

3. Electrochernical mechanism of corrosion – The formation of rust requires both oxygen and water. Since it is an electrochemical redox process, it requires both an anode and cathode in different places on the iron. The iron surface and a droplet of water on the surface form a tiny galvanic cell.

The region enclosed by water is exposed to low amount of oxygen and it act as anode. The remaining area has high amount of oxygen and it act as cathode. So based on oxygen amount, an electrochem leal cell is formed.
Fe(s) → Fe2+(aq) + 2e
O2(g) + 4H+(aq) + 4e → 2H2O(1)

4. At anode:
2Fe(s) → 2Fe2+(aq) + 4e E° = 1.23V
The electrons move through the iron metal from the anode to the cathode area where the oxygen dissolved in water is reduced to water.

5. At cathode:
The reaction of atmospheric carbondioxide with water gives carbonic acid which furnishes the H+ ions for reduction.
O2(s) + 4H+(g) + 4H+(aq) → 2H2O(1)
E° = 1.23 V
= + 1.67V

6. The electrical circuit is completed by the migration of ions through water droplet. The overall redox reaction is
2Fe(s) + O2(g) + 4H+(aq) → 2Fe3+(aq) + 2H2O(1).
E°= 0.44+ 1.23
= + 1.67 V

7. The positive emf value indicates that the reaction is spontaneous.

8. The Fe2+ ions are further oxidised to Fe3+ which on further reaction with oxygen to form rust.
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-55

Question 10.
Explain about the various protection methods to prevent corrosion.
1. Coating metal surface by paint

2. Galvanizing – By Coating with another metal such as zinc. Zinc is stronger oxidising agent than iron and hence it can be more easily corroded than iron. i.e., instead of iron, zinc is oxidised.

3. Cathodic protection: In this technique, unlike galvanizing, the entire surface of the metal to be protected need not be covered with a protecting metal instead, metals such as Mg (or) Zn which is corroded more easily than iron can be used as sacrificial anode and the iron material act as cathode. So iron protected but Mg or Zn gets corroded.

4. Passivation – The metal is treated with strong oxidising agent such as Conc. HNO3. As a result, a protective layer is formed on the surface of the metal.

5. Alloy formation – The oxidising tendency of iron can be reduced by forming its alloy with other more anodic metals. Example – Stainless steel, an alloy of Fe and Cr.

Question 11.
(a) Give reasons for the following

  • Rusting of iron is quicker in saline water than in ordinary water.
  • Aluminium metal cannot be produced by the electrolysis of aqueous solution of aluminium salt.

(b) Resistance of a conductivity cell filled with 0.1 M KCI solution is 1oo ohms. If the resistance of the sanie cell when filled with 0.02 M KCI solution is 520 ohms, calculate the conductivity and molar conductivity of 0.02 M KCI solution. Conductivity of 0.01 M KCI solution is 1.29 S m-1.
Answer:
(a)
1. It is because in saline water, there are inore H4 ions. Greater the number of H4 ions, quicker the rusting will take place.

2. It is because aluminium metal is more reactive than hydrogen and it will react with H2O.

(b)
Cell constant = Conductivity (k) x Resistance (R)
= 1.29 S m-1 x 100Ω
= 1.29 m-1 = 1.29 cm-1
λm = \(\frac { 100k }{ M }\)
k = \(\frac { 1 }{ R }\) x \(\frac { l }{ A }\)
k = \(\frac { 1 }{ 520Ω }\) x 1.29 cm-1, where
k = 2.48 x 10-3S cm-1
λm = \(\frac{100 \times 0.248 \times 10^{-2}}{0.02}\)
= 124 S cm2 mol1

Question 12.
1. State two advantages of H2 – O2 fuel cell over ordinary cell.
2. Silver is electron deposited on a metallic vessel of total surface area 900 cm2 by passing a current of 0.5 amp for two hours. Calculate the thickness of silver metal deposited. [Given: Density of silver = 10.5 g cm-3 Atomic mass of silver = 108 u. IF = 96500 C mol-1].
Answer:
1.

  • It is highly efficient and do not produce pollution.
  • The H2O so produced can be used by astronauts for drinking purpose.

2.
m = Z x l x t
m = \(\frac{108}{96500}\) x 0.5 x 2 x 60 x 60
= \(\frac{108 \times 5}{965 \times 10}\) x 2 x 6 x 6 = 4.03g
4.03g = V x d
4.03 g = V x 10.5 g cm-3
V = Area x thickness
v = 4.03
= 900 cm2 x thickness
Thickness = \(\frac{4.03}{10.5}\)
\(\frac{0.338 \mathrm{cm}^{3}}{900 \mathrm{cm}^{2}}\) = 4.26 x 10-4cm

Question 13.
Distinguish between Leclanche cell and Lead storage battery.
Answer:
Leclanche Cell

  1. It is a primary cell
  2. It is a non-rechargeable cell
  3. Anode : Zinc container
    Cathode : Graphite rod in contact with MnO2
  4. Electrolytes: Ammonium chloride and zinc chloride in water
  5. Emf of the cell = 1.5 V

Lead storage battery

  1. It is a secondary cell
  2. It is rechargeable cell
  3. Anode : Spongy lead
    Cathode : Lead plate bearing PbO2
  4. Electrolytes: 38% by mass of H2SO4 with density 1.2 g/ml
  5. emf of the cell 2 V.

Question 14.
Account for the following

  1. Aluminium undergo slow corrosion than iron.
  2. H2 – O2 fuel cell ¡s more useful than other cells.

Answer:
1. Aluminium, copper, silver also undergo corrosion but at a slower rate than iron. For eg., let us consider the reduction of Aluminium
Al(s) → Al3+(aq) + 3e
Al3+ which reacts with oxygen in air to form a protective coating of AI2O3. This coating act as a protective film for the inner surface. So further corrosion is prevented.

2. H2 – O2 fuel cell is more advanced. Because it is highly efficient. it is pollution free. In this, H2 – O2 fuel cell, energy of combustion of fuel is directly converted to electrical energy.

Common Errors

  1. Units of electrical quantities may get confused.
  2. Writing cell notation may be difficult.

Rectifications

1.Resistance – R ohm (Ω)
Potential difference – V = Volt
Amount of current – 1 = ampere
Specific resistance (ohm m) (Ω m)
Conductivity = Siemen = S
Specific conductance – k = S m-1
Molar conductance = S m2 mol-1
Equivalent conductance = S m2 gram equivalent-1
Cell constant = m-1

2. Easy way is (AC)
solid I aqueous solution II aqueous solution I soLid
Samacheer Kalvi 12th Chemistry Solutions Chapter 9 Electro Chemistry-56

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Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids

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Tamilnadu Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids

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Samacheer Kalvi 12th Chemistry Chapter 12 Carbonyl Compounds and Carboxylic Acids Text Book Evaluation

Samacheer Kalvi 12th Chemistry Carbonyl Compounds and Carboxylic Acids Multiple Choice Questions

Question 1.
The correct structure of the product ‘A’ formed in the reaction
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-1
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-2 .1
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-2

Question 2.
The formation of cyanohydrin from acetone is an example of …………..
(a) nucleophilic substitution
(b) electrophilic substitution
(c) electrophilic addition
(d) Nucleophilic addition
Answer:
(d) Nucleophilic addition

Question 3.
Reaction of acetone with one of the following reagents involves nucleophilic addition followed by elimination of water. The reagent is ………….
(a) Grignard reagent
(b) Sn / HCl
(c) hydrazine in presence of slightly acidic solution
(d) hydrocyanic acid
Answer:
(c) hydrazine in presence of slightly acidic solution

Question 4.
In the following reaction,
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-3
Product ‘X’ will not give
(a) Tollen’s test
(b) Victor meyer test
(c) Iodoform test
(d) Fehiing solution test
Answer:
(b) Victor meyer test
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-4
(x) reduces tollens reagent and Fehiing solution aind it also answers iodoform test.

Question 5.
In the following reaction,
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-5
(a) Formaldelyde
(b) diacetoneammonia
(c) hexamethylenetetraamlne
(d) oxime
Answer:
(c) hexamethylenetetraamlne
Hint:
X – HCHO
Y – (CH2)6 N4

Question 6.
Predict the product Z in the following series of reactions
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-6
iSamacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-7
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-7.1
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-8

Question 7.
Assertion: 2, 2 – dirnethyl propanoic acid does not give HVZ reaction.
Reason: 2 – 2, dimethyl propanoic acid does, not have – a hydrogen atom
(a) if both assertion and reason are true and reason is the correct explanation of assertion.
(b) if both assertion and reason are true but reason is not the correct explanation of assertion.
(c) assertion is true but reason is false
(d) both assertion and reason are false
Answer:
(a) if both assertion and reason are true and reason is the correct explanation of assertion.
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-9

Question 8.
Which of the following represents the correct order of acidity in the given compounds
(a) FCH2COOH > CH3COOH > BrCH2COOH > CICH2COOH
(b) FCH2COOH > CICH2COOH > BrCH2COOH > CH3COOH
(c) CH3COOH > CICH2COOH > FCH2COOH > Br – CH2COOH
(d) ClCH2COOH > CH3COOH > BrCH2COOH > ICH2COOH
Hint.
– I effect increases the acidity. If electronegativity is high, – I effect is also high.

Question 9.
Benzoic acid
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-10
(a) anilinium chloride
(b) O – nitro aniline
(c) benzene diazonium chloride
(d) m – nitro benzoic acid
Answer:
(c) benzene diazonium chloride
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-11

Question 10.
Ethanoic acid
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-12
2 – bromoethanoic acid. This reaction is called ……………
(a) Finkeistein reaction
(b) Haloform reaction
(c) Hell – Volhard – Zelinsky reaction
(d) none of these
Answer:
(c) Hell – Volhard – Zelinsky reaction

Question 11.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-13
(a) acetylchloride
(b) chioro acetic acid
(c) α – chiorocyano ethanoic acid
(d) none of these
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-14

Question 12.
Which one of the following reduces tollens reagent ………
(a) formic acid
(b) acetic acid
(c) benzophenone
(d) none of these
Answer:
(a) formic acid
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-15

Question 13.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-16
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-17
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-17.1
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-18

Question 14.
The TUPAC name of
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-19……………………
(a) but – 3 – enoicacid
(b) but 1 – ene – 4 – oicacid
(c) but 2 – ene – 1 – oic acid
(d) but – 3 – ene – 1 – oicacid
Answer:
(a) but – 3 – enoicacid
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-20

Question 15.
Identify the product formed in the reaction
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-21
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-22
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-22 .1
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-23Group is reduced to CH2 – (Wolff – Kishner reduction)

Question 16.
In which case chiral carbon is not generated by reaction with HCN
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-24
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-24.1
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-25

Question 17.
Assertion: p – N, N – dimethyl aminobenzaldehyde undergoes benzoin condensation
Reason: The aldehydic (- CHO) group is meta directing
(a) if both assertion and reason are true and reason is the correct explanation of assertion.
(b) if both assertion and reason are true but reason is not the correct explanation of assertion.
(c) assertion is true but reason is false
(d) both assertion and reason are false
Answer:
(b) if both assertion and reason are true but reason is not the correct explanation of assertion.
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-26

Question 18.
Which one of the following reaction is an example of disproportionation reaction …………….
(a) Aldol condensation
(b) cannizaro reaction
(c) Benzoin condensation
(d) none of these
Answer:
(b) cannizaro reaction
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-27

Question 19.
Which one of the following undergoes reaction with 50% sodium hydroxide solution to give the corresponding alcohol and acid …………
(a) Phenylmethanal
(b) ethanal
(c) ethanol
(d) methanol
Answer:
(a) Phenylmethanal

Question 20.
The reagent used to distinguish between acetaldehyde and benzaldehyde is ………..
(a) Tollens reagent
(b) Fehling’s solution
(c) 2, 4 – dinitrophenyl hydrazine
(d) semicarbazide
Answer:
(b) Fehling’s solution

Question 21.
Phenyl methanal is reacted with concentrated NaOH to give two products X and Y. X reacts with metallic sodium to liberate hydrogen X and Y are ………….
(a) sodiumbenzoate and phenol
(b) Sodium benzoate and phenyl methanol
(c) phenyl methanol and sodium benzoate
(d) none of these
Answer:
(c) phenyl methanol and sodium benzoate
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-28

Question 22.
In which of the following reactions new carbon – carbon bond is not formed?
(a) Aldol condensation
(b) Friedel craft reaction
(c) Kolbe’s reaction
(d) Wolf kishner reduction
Answer:
(d) Wolf kishner reduction

Question 23.
An alkene “A” on reaction with O3 and Zn – H2O gives propanone and ethanol in equimolar ratio. Addition of HCl to alkene “A” gives “B” as the major product. The structure of product “B” is ……………
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-29
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-30
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-31

Question 24.
Carboxylic acids have higher boiling points than aldehydes, ketones and even alcohols of comparable molecular mass. It is due to their ………………
(a) more extensive association of carboxylic acid via van der Waals force of attraction
(b) formation of carboxylate ion
(c) formation of intramolecular H – bonding
(d) formation of intermolecular H – bonding
Answer:
(d) formation of intermolecular H – bonding

Question 25.
Of the following, which is the product formed when cyclohexanone undergoes aldol condensation followed by heating?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-32
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-33
Hint:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-34

II. Answer the following questions.

Question 1.
How is propanoic acid is prepared starting from

  1. an alcohol
  2. an alkyihalide
  3. an alkene

Preparation of propanoic acid from,
Answer:
1. Alcohol:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-35

2. Alkylhalide:

Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-36

3. Alkene:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-37

Question 2.
A Compound (A) with molecular formula C2H3N on acid hydrolysis gives(B) which reacts with thionyichioride to give compound(C). Benzene reacts with compound (C) in presence of anhydrous AlCl3 to give compound (C). Compound (C) on reduction with gives (D). Identify (A), (B), (C) and D. Write the equations.
Answer:
1. Compound (A) with molecular formula C2H3N is methyl cyanide. (CH3CN)

2. Methyl cyanide (A) on hydrolysis gives acetic acid (B)
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-38

3. Acetic acid (B) with thionyl chloride to give acetyl chloride (C)
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-39

4. Benzene reacts with acetyl chloride (C) in the presence of anhydrous AlCl3 to give acetophenone (D)
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-40

5. Acetyl chloride (C) on reduced in the presence of Pd / H2 and Barium sulphate, to gives acetaldehyde (E).
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-41

Question 3.
Identify X and Y
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-42
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-43

Question 4.
Identify A, B and C
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-44
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-45

Question 5.
A hydrocarbon A(molecular formula C8H10) on ozonolysis gives B(C4H6O2 ) only. Compound C( C3H5Br) on treatment with magnesium in dry ether gives (D) which on treatment with CO2 followed by acidification gives (B). Identify A, B, C and D.
Answer:
1. Molecular formula C8H10 is 1, 2 – dicyclopropylethyne.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-46

2. 1, 2 – dicyclo propyl ethyne (A) on ozonolysis to give cyclo propyl carboxylic acid (B)
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-47

3. Compound C3H5Br is Bromo cyclo propane (C), which on reacts with Mg in dry ether gives Grignard reagent (D) which on treatment with CO2 followed by acidification gives cyclo propyl carboxylic acid (B).
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-48

Question 6.
Identify A, B, C and D
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-49
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-50

Question 7.
An alkene (A) on ozonolysis gives propanone and aldehyde (E). When (B) is oxidised (C) is obtained. (C) is treated with Br2 JP gives (D) which on hydrolysis gives (E). When propanone is treated with HCN followed by hydrolysis gives (F). Identify A, B, C, D and E and F.
Answer:
1. 2 – methyl – but – 2 – ene (A) on ozonolysis gives propanone and acetaldehyde (B)
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-51

2. Acetaldehyde (B) is oxidised to give acetic acid (C), which on further treated with Br2 / P give monobromo acetyl bromide (D) which on hydrolysis gives monobromo acetic acid (E).
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-52

3. Propanone is treated with HCN followed by hydrolysis to gives 2 – methyl – 2 – hydorxy propanoic acid (F)
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-53

Question 8
How will you convert benzaldehyde into the following compounds?

  1. benzophenone
  2. benzoic acid
  3. 2 – hydroxyphenylaceticacid.

Answer:
1. conversion of benzaldehyde into benzophenone.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-54

2. conversion of benzaldehyde into benzoic acid.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-55

3. conversion of benzaldehyde into 2 – hydroxy phenyl acetic acid.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-56

Question 9.
What is the action of HCN on

  1. propanone
  2. 2, 4 – dichiorobenzaldehyde.

Answer:
1. Propanone reacts with HCN.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-57

2. 2, 4 – dichlorobenzaldehyde reacts with HCN.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-58

Question 10.
A carbonyl compound A having molecular formula C5H10O forms crystalline precipitate with sodium bisuiphate and gives positive iodoform test. A does not reduce Fehling solution. Identify A.
Answer:
1. Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-59

2. Pentan – 2 – one gives positive iodoform test, but it does not reduce Fehling’s solution.

3. Hence carbonyl compound A having molecular formula C5H10O is pentan – 2 – one.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-60

Question 11.
Write the structure of the major product of the aldol condensation of benzaldehyde with acetone.
Answer:
Step 1:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-61

Step 2:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-62

Step 3:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-63

Step 4:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-64

Question 12.
How are the following conversions effected

  1. propanal into butanone
  2. Hex – 3 – yne into hexan – 3 – one.
  3. phenylmethanal into benzoic acid
  4. phenylmethanal into benzoin

Answer:
1. propanal into butanone
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-65

2. Hex – 3 – yne into hexan – 3 – one
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-66

3. phenylmethanal into benzoic acid
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-67

4. phenylmethanal into benzoin
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-68

Question 13.
Complete the following reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-69
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-70

Overall reaction:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-71

Question 14.
Identify A, B and C
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-72
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-73

Question 15.
When ketones are undergo oxidation, the C – C bond Is cleaved. When a strong oxidising agent is used to oxidise 2, 5 – dimethyl hexan – 3 – one mention the products with their names.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-74

Question 16.
How will you convert following conversion?

  1. Acetic acid into acetic anhydride
  2. Methyl acetate into ethyl acetate
  3. Methyl acetate into acetamide
  4. Acetyl chloride into acetophenone
  5. Sodium acetate into ethane
  6. Ethanal into lactic acid
  7. Toluene into benzoic acid
  8. Benzaldehyde into malachite green
  9. Benzaldehyde into Cinnamic acid
  10. Ethyne into acetaldehyde

Answer:
1. Conversion of Acetic acid into acetic anhydride
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-75

2. Conversion of Methyl cyanate into acetamide.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-76

3. Conversion of Methyl cyanate into acetamide.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-77

4. Conversion of Acetyl chloride into acetophenone.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-78

5. Conversion of Sodium acetate into ethane.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-79

6. Conversion of Ethanal into lactic acid.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-80

7. Conversion of Toluene into benzoic acid.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-81

8. Conversion of Benzaldehyde into malachite green.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-82

9. Conversion of benzaldehyde into cinnamic acid.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-83

10. Conversion of Ethyne into acetaldehyde.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-84

Samacheer Kalvi 12th Chemistry Carbonyl Compounds and Carboxylic Acids Evaluate yoursel

Question 1.
Write the IUPAC name for the following compound.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-85
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-86

Question 2.
Wrtie all possible structural isomers and position isomers for the ketone represented by the molecular formula C5H10O.
Answer:
Molecular formula C5H10O exhibits following possible ketone structural isomers and position isomers.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-87

Question 3.
What happens when the following alkenes are subjected to reductive ozonolysis.

  1. propene
  2. 1 – Butene
  3. Isobutylene

Answer:
1. propene
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-88

2. 1 – Butene
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-89

3. Isobutylene
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-90

Question 4.
What happens when n-propyl benzene is oxidised using H+ / KMnO4?
Answer:
When n – propyl benzene is oxidised with H+ / KMnO4 to gives benzoic acid.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-91

Question 5.
How will you prepare benzoic acid using Crignard reagent.
Answer:
Preparation of benzoic acid using Grignard reagent:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-92

Question 6.
Why acid anhydride are preferred to acyl chloride for carrying out acylation reactions?
Answer:
Acid anhydride are preferred to acyl chloride for carrying out acylation reactions. Because

  1. Easily available
  2. Cheap
  3. Easy to prepare
  4. Easily undergo acylation without irritating odours

Samacheer Kalvi 12th Chemistry Carbonyl Compounds and Carboxylic Acids Additional Questions

Samacheer Kalvi 12th Chemistry Carbonyl Compounds and Carboxylic Acids 1 Mark Questions and Answers

I. Choose the best answer.

Question 1.
Which one of the following aldehyde is derived from vitamin B, function as a co – enzyme?
(a) Pyridoxal
(b) Formaldehyde
(c) Ethanal
(d) Propanal
Answer:
(a) Pyridoxal

Question 2.
Which one of the following is used in the manufacture of Bakelite?
(a) Methanal
(b) Ethanal
(c) Phenyl methanal
(d) Butanal
Answer:
(a) Methanal

Question 3.
Which is used as a drug to reduce fever?
(a) Diethyl ether
(b) Acetone
(c) Acetophenone
(d) Paracetamol
Answer:
(d) Paracetamol

Question 4.
The IUPAC name of Acrolein is
(a) Prop – 2 – enal
(b) Propanal
(c) Ethenal
(d) 1 – butanal
Answer:
(a) Prop – 2 – enal

Question 5.
The IUPAC name of crotanaldehyde CH3 – CH = CH – CHO is …………….
(a) Prop – 2 – enal
(b) But – 2 – enal
(c) Ethenal
(d) Phenyl methanal
Answer:
(b) But – 2 – enal

Question 6.
The IUPAC name of is
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-93 …………………..
(a) Glyceraldehyde
(b) Acrolein
(c) 2, 3 – dihydroxy propanal
(d) Butanal
Answer:
(c) 2, 3 – dihydroxy propanal

Question 7.
Which one of the following is called Mesityl oxide?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-151
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-152

Question 8.
Which one of the following is called 3 – oxopentanal?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-153
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-154

Question 9.
Which one of the following is names as 3 – methyl cyclopentanone?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-155
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-156

Question 10.
Which one of the following is the hybridised state of C atoms in carbonyl carbon?
(a) sp
(b) sp3d
(c) sp3
(d) sp2
Answer:
(d) sp2

Question 11.
Which of the following reagent is used to get aldehyde from alcohol by oxidation method?
(a) Na2Cr2O7
(b) KMnO4
(c) PCC
(d) LiAlH4
Answer:
(c) PCC

Question 12.
The product formed when but – 2 – ene is on ozonolysis is ………….
(a) Propanone
(b) Methanal
(ç) Ethanal
(d) Butanal
Answer:
(ç) Ethanal

Question 13.
Which one of the following should be ozonolysed to get a mixture of ethanal and propanone?
(a) Propene
(b) But – 2 – ene
(c) Ethylene
(d) 2 – methyl – but – 2 – ene
Answer:
(d) 2 – methyl – but – 2 – ene

Question 14.
The products formed when propene is ozonolysed are …………….
(a) HCHO + CH3CHO
(b) CH3CHO
(c) HCOOH + CH3COOH
(d) CH3COCH3
Answer:
(a) HCHO + CH3CHO

Question 15.
Identify the products formed when But- 1-ene undergoes reductive ozonolysis?
(a) HCHO + CH3CHO
(b) HCHO + CH3CH2CHO
(c) CH3COCH3 + CH3CHO
(d) HCHO + CH3COCH3
Answer:
(b) HCHO + CH3CH2CHO

Question 16.
Which one of the following should be subjected to reductive ozonolysis to get only formal dehyde?
(a) CH ≡ CH
(b) CH3 – CH = CH2
(c) CH2 = CH2
(d) CH3 – CH3
Answer:
(c) CH2 = CH2

Question 17.
What are the products formed when Isobutylene is subjected to ozonolysis?
(a) HCHO + CH3CHO
(b) CH3COCH3 + HCHO
(c) CH3CHO + CH3COCH
(d) CH3COCH3 + CH3CH2CHO
Answer:
(b) CH3COCH3 + HCHO

Question 18.
Which one of the following is formed when acetylene is hydrolysed in the presence of HgSO4 and H2SO4?
(a) Ethanal
(b) Ethylene
(c) Ethane
(d) Ethanol
Answer:
(d) Ethanol

Question 19.
Hydrolysis of prop – 1 – yne in the presence of HgSO4 and H2SO4 gives ……………
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-157
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-158

Question 20.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-159
Answer:
(a) CaCO3 + H2
(b) CO2 + H2O + Ca
(c) HCHO + CaCO3
(d) CO + H2O + Ca(OH)2
Answer:
(c) HCHO + CaCO3

Question 21.
Calciwn acetate on dry distillation gives …………
(a) Acetic acid
(b) Propanone
(c) Ethanol
(d) Propanal
Answer:
(b) Propanone

Question 22.
Which of the following calcium salts are required to get ethanal by dry distillation process?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-160
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-161

Question 23.
The conversion of acetyl chloride to acetaldehyde by the action of Pd/BaSO4 is called ………………..
(a) Perkin’s reaction
(b) Stephens reaction
(c) Clemmenoon reduction
(d) Rosenmund reduction
Answer:
(d) Rosenmund reduction

Question 24.
Which of the following cannot be prepared by Rosenmund reduction method?
(a) Acetaldehyde
(b) Formaldehyde
(c) Ketone
(d) Both b & c
Answer:
(d) Both b & c

Question 25.
In Rosenmunds reduction, the action of BaSO4 is …………….
(a) Promoter
(b) Catalyst poison
(c) Positive catalyst
(d) Negative catalyst
Answer:
(b) Catalyst poison

Question 26.
Which one of the following is an intermediate product in Stephen’s reaction?
(a) Amines
(b) Amides
(c) Imines
(d) Amino acid
Answer:
(c) Imines

Question 27.
Which one of the following is used as selective reducing agent in the conversion of cyanide to aldehyde?
(a) Raney Ni
(b) LiAlH4
(c) SnCl2 / HCl
(d) DIBAL – H
Answer:
(d) DIBAL – H

Question 28.
Identify the product formed when benzaldehyde reacts with chromyl chloride?
(a) Benzoic acid
(b) Benzaldehyde
(c) Phenyl methanol
(d) Phenol
Answer:
(b) Benzaldehyde

Question 29.
The conversion reaction of Benzene to Benzaldehyde is known as ……………..
(a) Rosenmund reduction
(b) Stephen reduction
(c) Gattermann koch reaction
(d) Friedel – crafts reaction
Answer:
(c) Gattermann koch reaction

Question 30.
Which one of the following is used to convert acetyl chloride to acetone?
(a) CdCl2
(b) CrO2CI2
(c) Cu2CI2
(d) NaCl
Answer:
(a) CdCl2

Question 31.
Which one of the following is the best method to prepare alkyl aryl ketone and diaryl ketones?
(a) Stephen reaction
(b) Knoevengal reaction
(c) Ciemmenson reduction
(d) Friedel crafts reaction
Answer:
(d) Friedel crafts reaction

Question 32.
The product formed when Benzoyl chloride reacts with benzene is ………….
(a) Benzyl benzoate
(b) Benzophenone
(c) Benzyl chloride
(d) Benzyl alcohol
Answer:
(b) Benzophenone

Question 33.
Which one of the following is used as catalyst in Friedel Crafts reaction?
(a) Anhydrous ZnCl2
(b) Anhydrous CuCl2
(c) Anhydrous AlCl3
(d) Androus CaCl2
Answer:
(c) Anhydrous AlCl3

Question 34.
During nucleophilic addition reaction, the hybridisation of carbon changes from
(a) sp2 to sp3
(b) sp3 to sp2
(c) sp to sp3
(d) dsp2 to sp3
Answer:
(a) sp2 to sp3

Question 35.
Which one of the following is formed as a product when ethanal is treated with 2 equivalent of methanol?
(a) 1, 1 – dimethoxy methane
(b) 1 ,2 – dimethoxy ethane
(c) 1, 1 – dimethoxy ethane
(d) 1, 1 – diethoxy ethane
Answer:
(c) 1, 1 – dimethoxy ethane

Question 36.
Which aldehyde does not give aldimine with etheral ammonia solution?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-162
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-163

Question 37.
Identify the product formed when acetaldehyde reacts with ammonia?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-164
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-165

Question 38.
Which one of the following is formed when methanal reacts with ammonia?
(a) Tetramethylene hexamine
(b) Hexamethylene tetramine
(c) Formaldehyde ammonia
(d) Aldimine
Answer:
(b) Hexamethylene tetramine

Question 39.
Which one of the following is used as, an urinary antiseptic?
(a) Urotropine
(b) Urea formaldehyde
(c) Formalin
(d) Aldimm
Answer:
(a) Urotropine

Question 40.
Which one of the reactions gives an explosive RDX?
(a) Nitration of phenol
(b) Nitration of glycol
(c) Nitration of urotropine
(d) Nitration of glycerol
Answer:
(c) Nitration of urotropine

Question 41.
Which one of the following is called hydrobenzamide?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-166
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-167

Question 42.
Which one of the following is formed when benzaldehyde reacts with ammonia?
(a) Benzalamine
(b) Benzylamine
(c) Hydrobenzarnide
(d) Benzarnide
Answer:
(c) Hydrobenzarnide

Question 43.
Which rule governes the oxidation of unsymmetrical ketone?
(a) Markovnikoff’s rule
(b) Popoff s rule
(c) Antimarkovnikoff s rule
(d) Hund’s rule
Answer:
(b) Popoff s rule

Question 44.
What are the products formed when 2-butanonc is oxidised by conc – HNO3?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-168
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-169

Question 45.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-170
In this reaction A and B are …………
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-171
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-172

Question 46.
Name the product formed Acetaldehyde reacts with Zinc amalgam and conc.HCl?
(a) Propane
(b) Ethane
(c) Ethene
(d) Ethanal
Answer:
(b) Ethane

Question 47.
The reagent used in the Conversion of Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-173 group into – CH2 – group is …………..
(a) Zn + Hg / HCl
(b) NH2 – NH2 + C2H5ONa
(c) mg / Hg / H2O
(d) either (a) or (b)
Answer:
(d) either (a) or (b)

Question 48.
The product formed when Acetone is subjected to Clemmenson reduction is ……………..
(a) Acetic acid
(b) Propanoic acid
(c) Propane
(d) Propanal
Answer:
(c) Propane

Question 49.
Which one of the following is formed when acetone is treated with magnesium amalgam and water?
(a) Pinacol
(b) Acetyl acetone
(c) Aceto acetic ester
(d) 1 ,2 – dimethyl butane 1, 2 – diol
Answer:
(a) Pinacol

Question 50.
Which one of the following does not undergo halo form reaction?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-174
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-175

Question 51.
Which one of the following undergoes halo form reaction?
(a) HCHO
(b) C6H5CHO
(c) CH3CHO
(d) CH3 – CH2 – CH2OH
Answer:
(c) CH3CHO

Question 52.
Which one of the following is formed when acetaldehyde is warmed with dilute NaOH?
(a) But – 2 – enal
(b) Butan – 1 – al
(c) 3 – hydroxy butanal
(d) 2 – hydroxybutanoic acid
Answer:
(c) 3 – hydroxy butanal

Question 53.
The IUPAC naine of Acetaldol is ……………
(a) 3 – hydroxy butanal
(b) Aldol
(c) 2 – hydroxy butanal
(d) Butanal
Answer:
(a) 3 – hydroxy butanal

Question 54.
Which one of the following is formed when benzaldehyde reacts with acetaldehyde?
(a) Cinnamic acid
(b) Cinnamaldehyde
(c) Benzylidene acetone
(d) 3 – hydroxy propanal
Answer:
(b) Cinnamaldehyde

Question 55.
The crossed aldol condensation product of the reaction between Formaldehyde and Acetaldehyde is ………………
(a) 3 – hydroxy propanol
(b) 3 – hydroxy propanal
(c) 2 – hydroxy butanal
(d) 3 – hydroxy butanal
Answer:
(b) 3 – hydroxy propanal

Question 56.
The reaction of benzaldehyde with 50% NaOH is called …………..
(a) Benzoin condensation
(b) Claisen – schmidt reaction
(c) Perkin’s reaction
(d) Cannizaro reaction
Answer:
(d) Cannizaro reaction

Question 57.
The reaction of phenyl methanal and ethanal in the presence of dilute NaOH is known as ……………..
(a) Cannizaro reaction
(b) Aldol condensation
(c) Claisen – schmidt condensation
(d) Perkin’s reaction
Answer:
(c) Claisen – schmidt condensation

Question 58.
What is the second step in Cannizaro reaction mechanism?
(a) Attack of OH on carbonyl carbon
(b) Acid base reaction
(c) Protonation of carbonyl oxygen
(d) Hydride ion transfer
Answer:
(d) Hydride ion transfer

Question 59.
The first step take place in Cannizaro reaction mechanism is ……………..
(a) Aftack of OH on carbonyl carbon
(b) Protonation of carbonyl oxygen
(c) Acid base reaction
(d) Hydride ion transfer
Answer:
(a) Aftack of OH on carbonyl carbon

Question 60.
Which one of the following is formed when benzaldehyde reacts with alcoholic KOH?
(a) Benzyl alcohol
(b) Potassium henzoate
(c) Benzoin
(d) Benzoic acid
Answer:
(c) Benzoin

Question 61.
What is the name of the reaction of alcoholic KOH with Benzaldehyde’?
(a) Cannizaro reaction
(c) Benzoin condensation
(b) Perkin’s reaction
(d) Aldol condensation
Answer:
(c) Benzoin condensation

Question 62.
Which one of the following is formed when benzaldehyde reacts with acetic anhydride?
(a) Cinnamaldehyde + Acetaldehyde
(b) Cinnamic acid + Acetic acid
(c) Benzyl alcohol + Benzoic acid
(d) Benzal aniline + Acetic acid
Answer:
(b) Cinnamic acid + Acetic acid

Question 63.
What is the name of the reaction between Benzaldehyde and acetic anhydride?
(a) Peridn’s reaction
(b) Knoerenagal reaction
(c) Cannizaro reaction
(d) Kolbe’s reaction
Answer:
(a) Peridn’s reaction

Question 64.
What are the reagents required to prepare Benzal aniline (or) Schiff’s base?
(a) Benzyl amine + Ammonia
(b) Benzal amine + Ammonia
(c) Benzaldehyde + Aniline
(d) Phenol + Aniline
Answer:
(c) Benzaldehyde + Aniline

Question 65.
Which one of the following is the formula of Schiff’ s base’?
(a) C6H5 – NH NH2
(b) C6H5 CH = N – C6H5
(b) Perkin’s reaction
(d) Aldol condensation
Answer:
(b) C6H5 CH = N – C6H5

Question 66.
Which one of the following is used as a catalyst in Knoevenagal reaction?
(a) Pyrimidine
(b) Pyridine
(c) PCC
(d) CdCl2
Answer:
(b) Pyridine

Question 67.
Which one is formed when Benzaldehyde reacts with Malonic acid in the presence of Pyridine?
(a) Cinnamaldehyde
(b) Benzoin
(c) Hydrobenzamide
(d) Cinnamic acid
Answer:
(d) Cinnamic acid

Question 68.
Name the product formed when Benzaldehyde reacts with N,N – dimethyl aniline in the presence of conc.H2SO4?
(a) Cinnamic acid
(b) Skiffs base
(c) Malachite green dye
(d) p – hydroxy azodye
Answer:
(c) Malachite green dye

Question 69.
Identify the product formed when benzaldehyde reacts with chlorine in the presence of conc.FeCl3?
(a) m – chlorobenzaldehyde
(b) O – chlorobenzaldehyde
(c) p – chiorobenzaldehyde
(d) Benzoyl chloride
Answer:
(a) m – chlorobenzaldehyde

Question 70.
Identify the product formed when benzaldehyde reacts with chlorine in the absence of catalyst?
(a) p – chiorobenzaldehyde
(b) O – chiorobenzaldehyde
(c) Benzoyl chloride
(d) m – chlorobenzaldehyde
Answer:
(c) Benzoyl chloride

Question 71.
Which one of the following is used to test ketones?
(a) lodoform test
(b) Tollen’s reagent test
(c) Fehling’s solution test
(d) Benedict’s solution test
Answer:
(a) lodoform test

Question 72.
Which one of the following is not used to identify aldehydes?
(a) Benedict’s solution test
(b) Fehling’s solution test
(c) Dye test
(d) Tollen’s reagent test
Answer:
(c) Dye test

Question 73.
What is the colour change take place when Fehling’s solution is added to an aldehyde?
(a) Red to blue
(b) Blue to red
(c) Red to green
(d) Green to blue
Answer:
(b) Blue to red

Question 74.
Which one of the following is used for preserving biological specimens?
(a) Urotropine
(b) Formalin
(c) Schiff’s base
(d) Benzoin
Answer:
(b) Formalin

Question 75.
Which one of the following is formed when phenol is heated with formalin?
(a) Bakelite
(b) PVC
(c) Polyurethane
(d) Polyester
Answer:
(a) Bakelite

Question 76.
RDX is otherwise named as …………….
(a) Cyclonite
(b) Cyclohexane
(c) 1, 4 – dione
(d) Cyclohexanol
Answer:
(a) Cyclonite

Question 77.
Which one of the following is used as a hypnotic?
(a) Acetaldehyde
(b) Formalin
(c) Paraldehyde
(d) Formaldehyde
Answer:
(c) Paraldehyde

Question 78.
Which one of the following is used in silvering of mirrors?
(a) Paraldehyde
(b) Benzaldehyde
(c) Acetone
(d) Acetaldehyde
Answer:
(d) Acetaldehyde

Question 79.
Which one of the following is used in the manufacture of smokeless powder (cordite)?
(a) Acetone
(b) Acetaldehyde
(c) Acetic acid
(d) Formaldehyde
Answer:
(a) Acetone

Question 80.
Which one of the following is used as nail polish remover?
(a) CH3CHO
(b) HCHO
(c) CH3COCH3
(d) C6H5COCH3
Answer:
(c) CH3COCH3

Question 81.
Which is used in the manufacture of thermosoftening plastic perspex?
(a) Acetaldehyde
(b) Formaldehyde
(c) Acetone
(d) Acetophenone
Answer:
(c) Acetone

Question 82.
Which of the following is called hyphone?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-176
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-300

Question 83.
Which of the following is used in the preparation of benzhydrol drop?
(a) Benzaldehyde
(b) Benzophenone
(c) Acetophenone
(d) Benzoin
Answer:
(b) Benzophenone

Question 84.
Consider the following statements.
(i) Terminal olefins gives Formaldehyde as one of the product
(ii) Oxidation of alcohols using pcc yield carboxylic acids
(iii) Catalytic dehydrogenation of alcohols give either aldehyde or ketone.
Which of the above statement is/are not correct?
(a) (ii) only
(b) (i) & (iii)
(c) (ii) & (iii)
(d) (ii) only
Answer:
(a) (ii) only

Question 86.
Consider the following statements:
(i) Formaldehyde is a gas at room temperature and acetaldehyde is a volatile liquid.
(ii) The oxidation of symmetrical ketones is governed by Popoti’s rule.
(iii) Aliphatic aldehyde react with primary amines in the presence of base gives Schiff’s base.
Which of the above statement is/are not correct?
(a) (i) only
(b) (ii) only
(c) (ii) & (iii)
(d) (i) & (ii)
Answer:
(c) (ii) & (iii)

Question 87.
The JUPAC name of isSamacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-177
(a) Benzene carboxylic acid
(b) Benzoic acid
(c) 2 – phenyl ethanoic acid
(d) 2 – phenyl acetic acid
Answer:
(c) 2 – phenyl ethanoic acid

Question 88.
The formula of malonic acid is …………
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-178
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-301

Question 89.
The IUPAC name of HOOC – (CH2)4 – COOH is ………………
(a) Adipic acid
(b) Butane dioic acid
(c) Hexane diolc acid
(d) Glutaric acid
Answer:
(c) Hexane diolc acid

Question 90.
Which one of the following is the formula of Succinic acid?
(a) HOOC – CH2 – COOH
(b) HOOC – (CH2)2 – COOH
(c) HOOC – (CH2)4 – COOH
(d) HOOC – (CH)3 – COOH
Answer:
(b) HOOC – (CH2)2 – COOH

Question 91.
Consider the following statements.
(i) In – COOH group, the centre carbon atom and both the oxygen atoms are in sp3 hybridisation.
(ii) RCOOH can be represented as a resonance hybrid of two canonical structures.
(iii) Carboxylic carbon is less electrophilic than carbonyl carbon because of the reasonan structure.
Which of the above statement is/are correct?
(a) (iii) only
(b) (ii) only
(c) (i) only
(d) (i) & (ii)
Answer:
(b) (ii) only

Question 92.
Which one of the following reacts with methyl magnesium iodide followed by acid hydrolysis yield acetic acid?
(a) Solid CO2
(b) HCHO
(c) CH3CHO
(d) CH3CN
Answer:
(a) Solid CO2

Question 93.
Which one of the following acid cannot be prepared from grignaid reagent by the action of dry ice?
(a) CH3COOH
(b) C6H5COOH
(c) CH3 – CH2COOH
(d) HCOOH
Answer:
(d) HCOOH

Question 94.
Which one of the following is formed as a product when Benzoic anhydride is hydrolysed?
(a) Benzoin
(b) Benzoic acid
(c) Benzyl alcohol
(d) Benzaldehyde
Answer:
(b) Benzoic acid

Question 95.
Consider the following statements.
(i) Carboxylic acids have higher boiling point than aldehyde and ketone due to the association of carboxylic acid.
(ii) Vinegar is 60 to 80% solution of acetic acid in water
(iii) Higher carboxylic acids are insoluble in water due to increased hydrophobic interaction of hydrocarbon part.
Which of the above statement is/are not correct’?
(a) (iii) only
(b) (ii) only
(c) (i) only
(d) (i) & (iii)
Answer:
(b) (ii) only

Question 96.
Which one of the following is formed when ethanoic acid is treated with HI and Red phosphorous?
(a) Ethane
(b) Ethene
(c) Ethyne
(d) Methane
Answer:
(a) Ethane

Question 97.
What will be the product formed when sodium acetate is treated with sodalime?
(a) C2H6
(b) CH4
(c) CH3COOH
(d) (CH3CO)2O
Answer:
(b) CH4

Question 98.
The reaction of electrolysis of sodium acetate to form ethane is known as ………………..
(a) Kolbe’s electrolytic decarboxylation
(b) Perkin’s reaction
(c) Clemmenson reaction
(d) Cannizaro reaction
Answer:
(a) Kolbe’s electrolytic decarboxylation

Question 99.
Sodium formate solution on electrolysis gives at anode.
(a) Methane + CO2
(b) Ethane + CO2
(c) H2 + CO2
(d) Formic acid
Answer:
(c) H2 + CO2

Question 100.
Which one of the following is formed when acetic acid is heated with phosphorous pentoxide?
(a) CH3COCH3
(b) CH3CONH2
(c) CH4
(d) (CH3CO)2O
Answer:
(d) (CH3CO)2O

Question 101.
The reaction of acetic acid with Cl2 and red phosphorous is named as ………………
(a) Kolbe’s reaction
(b) Reimer – Tiemann reaction
(c) HeII – volhard – zelinsky reaction
(d) Knoevenagal reaction
Answer:
(c) HeII – volhard – zelinsky reaction

Question 102.
Which one of the following does not undergo friedel crafts reaction?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-179
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-180

Question 103.
Which one of the following can act as a reducing agent?
(a) C6H5COOH
(b) HCOOH
(c) CH3COOH
(d) CH3 – CH2COOH
Answer:
(b) HCOOH

Question 104.
Consider the following statements.
(i) Carboxylic acids turn red litmus blue.
(ii) Carboxylic acids give brisk efferrescence with NaHCO3
(iii) Carboxylic acid is warmed with alcohol and conc. H2SO4 gives fruity odour ester.
Which of the above statement is/are not correct?
(a) (i) only
(b) (ii) only
(c) (iii) only
(d) (i) & (iii)
Answer:
(a) (i) only

Question 105.
Which is one the correct order of strength of carboxylic acid?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-182
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-181
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-183

Question 106.
The correct increasing order acid strength of carboxylic acid is …………
(a) F – CH2 – COOH > I – CH2 – COOH > CI – CH2 – COOH > Br – CH2 – COOH
(b) Br – CH2 – COOH > F – CH2COOH > I – CH2COOH > Cl – CH2 – COOH
(c) F – CH2 – COOH > CI – CH2COOH > Br – CH2COOH > I – CH2COOH
(d) Br – CH2 – COOH > CI – CH2 – COOH > I – CH2COOH > F – CH2COOH
Answer:
(c) F – CH2 – COOH > CI – CH2COOH > Br – CH2COOH > I – CH2COOH

Question 107.
The increasing order of acid strength is ………….
(a) CH3COOH > CI2CHCOOH > CCI3CCOOH > ClCH2COOH
(b) CI3CCOOH > CI2CH COOH > CICH2COOH > CH3COOH
(c) CH2COOH < CI2CH COOH < CCl3CCOOH < ClCH2COOH
(a) Cl2CH – COOH < CCI3COOH < ClCH2COOH < CH3COOH
Answer:
(b) CI3CCOOH > CI2CH COOH > CICH2COOH > CH3COOH

Question 108.
The relative acidities of various organic compounds are ……………
(a) RCOOH > ArOH > H2O > ROH > RC ≡ CH
(b)RCCH > ArOH > ROH > H2O > RCOOH
(c) ROH > R ≡ CH > ArOH > RCOOH > H2O
(d) H2O > ROH > RCOOH > ArOH > RC ≡ CH
Answer:
(a) RCOOH > ArOH > H2O > ROH > RC ≡ CH

Question 109.
The correct order of the basicity of the leaving group is …………..
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-184
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-185

Question 110.
The conversion of Ethyl acetate to propyl acetate by the action of propyl alcohol is named as
(a) Esterification
(b) Transesterfication
(c) Acid hydrolysis of ester
(d) Alkaline hydrolysis of ester
Answer:
(b) Transesterfication

Question 111.
Ethyl acetate undergoes self condensation in the presence of strong base to give ………………..
(a) Ethyl aceto acetate + Ethanol
(b) Ethyl aceto acetate + Acetic acid
(c) Ethyl aceto propionate + propanol
(d) Ethyl ethanoate + Ethanoic acid
Answer:
(a) Ethyl aceto acetate + Ethanol

Question 112.
Methyl cyanide on acid hydrolysis gives
(a) Acetyl chloride
(b) Acetic acid
(c) Acetamide
(d) Acetic anhydride
Answer:
(c) Acetamide

Question 113.
Which one of the following is the product formed when acetamide is treated with P2O5?
(a) Acetonitrile
(b) Methylamine
(c) Ethyl cyanide
(d) Methanamine
Answer:
(a) Acetonitrile

Question 114.
Identify the product formed when acetamide reacts with LiAIH4?
(a) Methyl amine
(b) Aceto nitrite
(c) Ethyl amine
(d) Ethylcyanide
Answer:
(c) Ethyl amine

Question 115.
Which one of the following is used as a medicine in the treatment of gout?
(a) CH3COOH
(b) C6H5COOH
(c) CH3CONH2
(d) HCOOH
Answer:
(d) HCOOH

Question 116.
Which one of the following is used as a coagulating agent for rubber latex?
(a) Ethanoyl chloride
(b) Butanoic acid
(c) Methanoic acid
(d) Benzoic acid
Answer:
(c) Methanoic acid

Question 117.
Which one of the following is used as food preservative?
(a) Sodium formate
(b) Sodium acetate
(c) Sodium benzoate
(d) Acetamide
Answer:
(c) Sodium benzoate

Question 118.
Which one of the following is used in detection and estimation of – OH and – NH2 group in organic compounds?
(a) Acetic anhydride
(b) Acetyl chloride
(c) Acetamide
(d) Ethyl acetate
Answer:
(b) Acetyl chloride

Question 119.
Which one of the following is used in the preparation of medicine like aspirin and phenacetin?
(a) Acetyl chloride
(b) Acetic acid
(c) Acetamide
(d) Acetic anhydride
Answer:
(d) Acetic anhydride

Question 120.
Which one of the following is used in the preparation of Artificial fruit essences?
(a) Ethanoic acid
(b) Acetamide
(c) Ethyl acetate
(d) Acetic anhydride
Answer:
(c) Ethyl acetate

Question 121.
Acetone and acetaldehyde are differentiated by ………….
(a) NaOH + I2
(b) Ag(NH3)2+ (Tollens’s reagent)
(c) I2
(d) NaOH + NH3
Answer:
(b) Ag(NH3)2+ (Tollens’s reagent)

Question 122.
The most suitable reagent for the conversion of is R – CH2OH → RCHO …………..
(a) KMnO4
(b) K2Cr2O7
(c) CrO3
(d) Pcc
Answer:
(d) Pcc

Question 123.
Which of the following will not give iodoform test?
(a) Isopropyl alcohol
(b) Ethanol
(c) Eth anal
(d) Benzyl alcohol
Answer:
(d) Benzyl alcohol

Question 124.
Products of the following reaction …….
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-186
(a) CH3CHO + CH3CH = CHO
(b) CH3COOH + CH3CH2CHO
(c) CH3COOH + HOOCCH2CH3
(d) CH3COOH + CO2
Answer:
(b) CH3COOH + CH3CH2CHO

Question 125.
Identify the reagents X and Y are ………………
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-187
(a) X = MgCl2 Y = CH3CH = CH2
(b) X = CH3 MgCI Y = C6H5COCH3
(c) X = CH3 MgCI Y = (CH3)3C – OH
(d) X = C6H5 MgCI Y = (CH3)3C – OH
Answer:
(c) X = CH3 MgCI Y = (CH3)3C – OH

Question 126.
Reduction of > C = O to – CH2 can be carried out with ……………
(a) Ni
(b) Na/C2H5OH
(c) NH2 – NH2 + C2HONa
(d) LiAIH4
Answer:
(c) NH2 – NH2 + C2HONa

Question 127.
Which of the following is incorrect?
(a) FeCl3 is used in the detection of phenols
(b) Fehlings solution is used in the detection of aldehyde
(c) Tollen’s reagent is used in the detection of unsaturation
(d) NaHSO3 is used in the detection of carbonyl compounds
Answer:
(c) Tollen’s reagent is used in the detection of unsaturation

Question 128.
Which of the following products is formed when Benzaldehyde is treated with CH3MgBr and the addition product so obtained is subjected to acid hydrolysis?
(a) Secondary alcohol
(b) Primary alcohol
(c) Phenol
(d) Tertiary alcohol
Answer:
(a) Secondary alcohol

Question 129.
The reagent used to distinguish formaldehyde and acetaldehyde is …………..
(a) Tollen’s reagent
(b) Fehling’s solution
(c) Schiff’s reagent
(d) Caustic soda solution
Answer:
(d) Caustic soda solution

Question 130.
Which of the followìng will not give halo form test?
(a) Ethanal
(b) Ethanol
(c) Propan – 2 – one
(d) Pentan – 3 – one
Answer:
(d) Pentan – 3 – one

Question 131.
Which of the following does not turn schiff’s reagent to pink?
(a) Formaldehyde
(b) Benzaldehyde
(c) Acetone
(d) Acetaldehyde
Answer:
(c) Acetone

Question 132.
Which will not give acetamide on reaction with ammonia?
(a) Acetic acid
(b) Acetyl chloride
(c) Acetic anhydride
(d) methyl formate
Answer:
(d) methyl formate

Question 133.
The addition of HCN to carbonyl compounds is an example of ………….. reaction.
(a) N ucleophilic substitution
(b) Electrophil ic addition
(c) Nucleophilic addition
(d) Electrophilic substitution
Answer:
(c) Nucleophilic addition

Question 134.
Cinnamic acid is formed when C6H5CHO condenses with (CH3CO)2O in the presence of ……………
(a) Conc.H2SO4
(b) CH3COONa
(c) Na metal
(d) Anhydrous ZnCI2
Answer:
(b) CH3COONa

Question 135.
The molecular formula of Urotropine is …………..
(a) (CH2)6N4
(b) (CH2)4N6
(c) (CH2)2N2
(d) (CH2)6N6
Answer:
(a) (CH2)6N4

Question 136.
Bakelite is a thermosetting plastic produced by …………….
(a) HCHO + C6H5CH2OH
(b) HCHO + C6H5OH
(c) CH3CHO + C6H5OH
(d) HCHO + CH3COCH3
Answer:
(b) HCHO + C6H5OH

Question 137.
Aldehydes and ketones are reduced to hydrocarbon by the action of ………….
(a) LiAlH4
(b) H2 / Pd + BaSO4
(c) Na + Hg/HCI
(d) NH2 – NH2 / C2H5ONa
Answer:
(d) NH2 – NH2 / C2H5ONa

Question 138.
What is the name of the reaction when benzaldehyde changes into Benzyl alcohol?
(a) Friedel – crafts reaction
(b) Kolbe’s reaction
(c) Cannizaro reaction
(d) Wurtz reaction
Answer:
(c) Cannizaro reaction

Question 139.
Aldehyde turns pink with …………..
(a) Benedict solution
(b) Schiff ‘s base
(c) Fehiing solution
(d) Tollen’s reagent
Answer:
(b) Schiff ‘s base

Question 140.
Which of the following would undergo aldol condensation?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-188
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-189

Question 141.
Which one of the following undergoes reaction with 50% NaOH solution to give the corresponding alcohol and acid?
(a) Butanal
(b) Phenyl methanal
(c) Phenol
(d) Ethanal
Answer:
(b) Phenyl methanal

Question 142.
Hexa methylene tetramine is used as ………………
(a) analgesic
(b) antipyretic
(c) Urinary antiseptic
(d) all of these
Answer:
(c) Urinary antiseptic

Question 143.
The compound which gives acetone on ozonolysis is …………
(a) CH3 – CH = CH – CH3
(b) (CH3)2C = C(CH3)2
(c) C6H5CH = CH2
(d) CH3 – CH = CH2
Answer:
(b) (CH3)2C = C(CH3)2

Question 144.
Predict the product X in the sequence of the reaction
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-190
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-191
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-192

Question 145.
From which of the following, tertiary butyl alcohol is obtained by the action of methyl magnesium iodide?
(a) HCHO
(b) CH3COCH3
(c) CH3CHO
(d) CO2
Answer:
(b) CH3COCH3

Question 146.
Tdentifý the product “C” in the sequence of the reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-193
(a) CH3CH2NH2
(b) CH3CH2OH
(c) CH2 = CH2
(d) CH3CHO
Answer:
(c) CH2 = CH2

Question 147.
O3 reacts with CH2 = CH2 to form ozonide. On hydrolysis it forms …………….
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-194
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-195

Question 148.
Ethyne on reaction with water in the presence of HgSO4 and H2SO4 gives …………….
(a) Propanone
(b) Ethanal
(c) Ethane
(d) Ethanol
Answer:
(b) Ethanal

Question 149.
Which of the aldehyde is most reactive?
(a) C6H5CHO
(b) CH3CHO
(c) HCHO
(d) CH3 – CH2 – CHO
Answer:
(c) HCHO

Question 150.
Acetaldehyde does not answer
(a) lodoform test
(b) Lucas test
(c) Benedict test
(d) Tollen’s reagent test
Answer:
(b) Lucas test

II. Fill In the blanks.

  1. The aldehyde Pyridoxal function as a ………….
  2. p – acetylated amino phenol is used to reduce ………….
  3. The TUPAC name of CH3 – CH = CH – CHO is ………….
  4. The TUPAC name of CH2 = CH – CHO is ………….
  5. The formula of mesityl oxide is ………….
  6. The name ofSamacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-196 is ………….
  7. But – 2 – ene gives 2 moleafethanal by ………….
  8. …………. Olefines give formaldehyde as one of the product.
  9. Hydration of …………. in the presence of 40% dilute sulphuric acid and 1% HgSO4 gives Ethanal.
  10. Calcium formate on …………. gives methanal and CaCO3.
  11. Dry distillation of …………. gives propanone and CaCO3.
  12. Tn Rosenmund’s reduction reaction …………. is the catalyst and …………. is the catalytic poison.
  13.  …………. selectively reduces alkyl cyanide to form imines which on hydrolysis gives aldehyde.
  14. Side chain oxidation of toluene in the presence of KMnO4 gives ………….
  15. The oxidising agent used to convert toluene to benzaldehyde is ………….
  16. Acetyl chloride reacts with …………. to form acetone.
  17. Addition of …………. finds application in. the separation and purification of carbonyl compounds.
  18. Aliphatic aldehyde except …………. react with an ethereal solution of ammonia to form aldimines.
  19. Formaldehyde reacts with ammonia to form …………. which is used to treat urinary infection.
  20. Nitration of Urotropine under controlled condition gives an explosive ………….
  21. RDX is also called …………. or ………….
  22. With ammonia, benzaldehyde form a complex condensation product called ………….
  23. The oxidation of unsymmetrical ketone is governed by ………….
  24. The reducing agent used in Clemmensen reduction is ………….
  25. The reducing agent used in woif-kishner reduction is ………….
  26. Symmetric diols are called ………….
  27. Aldehydes which do not have …………. undergo disproportionation reaction (or) cannizaro reaction.
  28. The reagent used in the conversion of Benzaldehyde to Benoin is ………….
  29. In Knoevenagal reaction …………. act as the basic catalyst.
  30. The formula of Benzal aniline (or) Schiffs base is ………….
  31. Benzaldehyde condenses with N, N – dimethyl aniline in the presence of strong acids to form ………….
  32. …………. is ammoniacal silver nitrate solution.
  33.  …………. is a mixture of CuSO4 + Sodium citrate + NaOH.
  34. 40% aqueous solution of formaldehyde is known as …………..
  35. Paraldehyde is used in medicine as ………….
  36. Acetone is used in the manufacture of thermo softening plastic ………….
  37. …………. is used in perfumery and as a hypnotic under the name hyphone.
  38.  …………. cannot be prepared by grignard reagent since the acid contains only one carbon atom.
  39. Most of carboxylic acid exist as …………. in its vapour state.
  40. …………. is 6 to 8% solution of acetic acid in water.
  41. …………. is used to convert acetic acid to ethane at 473 K.
  42. …………. reaction is generally used for the preparation of esters of higher alcohol from that of a lower alcohol.
  43. Formic acid is used in medicine for treatment of ………….
  44. The conversion of acetamide to methylamine by the action of caustic alkali and Bromine is known as ………….
  45. …………. is used as food preservative.
  46. …………. is used in the detection and estimation of – OH, – NH2, groups in organic compounds.
  47. …………. is used in the preparation of artificial fruit essences.
  48. The conversion of Benzene to Benzaldehyde by the action of carbon monoxide and HCl is known as ………….
  49. The product formed when formaldehyde condensed with acetone is ………….
  50. Benzaldehyde condenses with acetaldehyde to form ………….

Answer:

  1. Coenzyme
  2. Fever
  3. But – 2 – enal
  4. Prop – 2 – enal
  5. (CH3), C = CHCOCH3
  6. 3-Oxo pentanal
  7. Ozonolysis
  8. Terminal
  9. Ethyne
  10. Dry distillation
  11. Calcium ethanoate
  12. Pd, BaSO4
  13. Diisobutvl aluminum hydride
  14. Benzoic acid
  15. CrO2Cl2 Chromyl chloride
  16.  Dimethyl cadmium
  17.  NaHSO3
  18. Formaldehyde
  19. Urotropinc (or) Hexamethylene tetramine
  20. RDX (or) Research and development explosive
  21. Cyclonite(or)cyclotrimethylene trinitramine
  22. Hydrobenzamide
  23. Popott’s rule
  24. Zn + Hg / conc.HCl
  25. NH2 – NH2 + C2H5ONa
  26. Pinacol
  27. a – hydrogen atom
  28. Alcoholic KCN
  29. Pyridine
  30. C6H5CH = N – C6H5
  31. Triphenyl methane dye or malachite green dye
  32.  Tollen’s reagent
  33. Benedict’s solution
  34. Formalin
  35. Hypnotic
  36. Perspex
  37. Acetophenone
  38. Formic acid HCOOH
  39. Dimer
  40. Vinegar
  41. HI + Red P
  42. Transesterification
  43. Gout
  44. Hoff mann’s degradation
  45. Sodium benzoate
  46. Acetyl chloride
  47. Ethyl acetate
  48. Gattermann – koch reaction
  49. 4 – hydroxy – butane – 2 – one
  50. Cinnamaldehyde

III. Match the following.
Match the column I and II using the code given below the column.

Question 1.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-197
Answer:
(a) 3 2 4 1

Question 2.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-198
Answer:
(b) 3 1 4 2

Question 3.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-199
Answer:
(c) 3 4 1 2

Question 4.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-200
Answer:
(a) 2 3 4 1

Question 5.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-201
Answer:
(d) 3 4 1 2

Question 6.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-202
Answer:
(a) 2 3 1 4

Question 7.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-203
Answer:
(a) 4 3 1 2

Question 8.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-204
Answer:
(a) 3 4 1 2

Question 9.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-205
Answer:
(a) 2 4 1 3

Question 10.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-206
Answer:
(a) 3 1 4 2

Question 11.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-207
Answer:
(a) 2 4 1 3

Question 12.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-208
Answer:
(a) 2 3 4 1

IV. Assertion and reasons.

Question 1.
Assertion(A): In Rosenmund’s reduction, BaSO4 act as catalyst pòison.
Reason (R): In Rosenmund’s reduction, BaSO4 act as catalytic poison to pd catalyst so that aldehyde cannot be further reduced ti alcohol.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not correct explanation of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 2.
Assertion(A): Aldehydes and ketones have high high boiling point as compared to hydrocarbon and ether of comparable molecular mass.
Reason (R): It is due to weak molecular association in aldehydes and ketones arising out of the dipole – dipole interactions.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are wrong
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 3.
Assertion(A): The boiling point of aldehydes and ketones are much lower those of corresponding alcohols and carboxylic acids.
Reason (R): Alcohols and carboxylic acids possess intermolecular hydrogen bonding and so have high boiling point.
(a) Both A and R are correct but R is not the correct explanation of A.
(b) Both A and R are correct and R ¡s the correct explanation of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(b) Both A and R are correct and R ¡s the correct explanation of A

Question 4.
Assertion(A): Aldehydes and ketones have high dipole moment.
Reason (R): The carbonyl group of aldehydes and ketones contain a double bond between carbon and oxygen. Oxygen is more electronegative than carbon and it attracts the shared pair of electron which makes the carbonyl group as polar.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not the correct explanation of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 5.
Assertion(A): Addition of sodium bisuiphite finds application in the separation and purification of carbonyl compound.
Reason (R): The bisuiphite addition compound is water soluble and the solution is treated with mineral acid to regenerate the carbonyl compounds.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not the correct explanation of A
(c) Both A and R are wrong
(d) A is correct but R is wrong
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 6.
Assertion(A): Acetaldehyde does not undergo cannizaro reaction.
Reason (R): Cannizaro reaction is a characteristic of aldehyde having no α – H atom. Acetaldehyde contains 3 α – H atoms.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R. is not correct explanation of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 7.
Assertion(A): Acetaldehyde and acetone are readily undergo aldol condensation reaction in the presence of dilute base.
Reason (R): Aldehyde or ketone having α – hydrogen atom add together to give aldol or ketol.
(a) Both A and R are correct but R is not the correct explanation of A.
(b) Both A and R are correct and R is the correct explanation of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(b) Both A and R are correct and R is the correct explanation of A

Question 8.
Assertion(A): Carboxylic acids have higher boiling point than aldehyde and ketone of comparable molecular mass.
Reason (R): This is due to more association of carboxylic acid. Molecules through intermolecular hydrogen bonding.
(a) Both A and R are correct but R is not correct explanation of A.
(b) Both A and R are correct and R is the correct explanation of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(b) Both A and R are correct and R is the correct explanation of A

Question 9.
Assertion(A): Lower aliphatic carboxylic acids arc miscible with water but higher carboxylic acids are insoluble in water.
Reason (R): Lower carboxylic acids are able to form hydrogen bond with water whereas higher carboxylic acids have increased hydrophobic interaction of hydrocarbon part.
(a) Both A and R are correct and R is the correct explanation Of A.
(b) Both A and R are correct but R is not correct explanation of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation Of A.

Question 10.
Assertion(A): Carboxylic acid do not give the characteristic reaction of carbonyl group as given by aldehyde and ketone.
Reason (R): The carbonyl carbon of carboxylic acid is involved in resonance.
(a) Both A and R are correct but R is not correct explanation of A.
(b) Both A and R are correct and R is the correct explanation of A
(c) Both A and R are correct and R is the correct explanation of A.
(d) Both A and R are correct but R is not correct explanation of A
Answer:
(c) Both A and R are correct and R is the correct explanation of A.

Question 11.
Assertion(A): Benzoic acid does not undergo friedel crafts reaction.
Reason (R): This is due to the strong deactivating nature of the carboxyl group
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and R are correct but R is not the correct explanation of A
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 12.
Assertion(A): Formic acid can act as a strong reducing agent
Reason (R): Formic acid contains both aldehyde as well as an acid group.
(a) Both A and R are wrong
(b) A is correct but R is wrong
(c) A is wrong but R is correct
(d) Both A and R are correct and R is the correct explanation of A.
Answer:
(d) Both A and R are correct and R is the correct explanation of A.

Question 13.
Assertlon(A): Trichioro acetic acid is more acidic than acetic acid.
Reason (R): Cl is a electron withdrawing group and acidity increases with increasing number of electron withdrawing substituents on the α – carbon.
(a) Both A and R are correct and R is the correct reason of A.
(b) Both A and R are correct but R is not correct reason of A.
(c) A is correct but R is wrong
(d) A is wrong but R is correct.
Answer:
(a) Both A and R are correct and R is the correct reason of A.

V. Find the odd one out and give the reasons.

Question 1.
(a) Methanal
(b) Ethanal
(c) Phenyl metbanal
(d) Prop – 2 – enal
Answer:
(c) Phenyl metbanal
It is an aromatic aldehyde where as others are aliphatic aldehydes.

Question 2.
(a) Formic acid
(b) Acetic acid
(c) Benzoic acid
(d) Propanoic acid
Answer:
(d) Propanoic acid
It can act as reducing agent where as other acids are not act as reducing agents.

Question 3.
(a) HCHO
(b) C6H5CHO
(c) CCI3CHO
(d) CH3CHO
Answer:
(d) CH3CHO
CH3CHO. It contains α – H atom and undergoes aldol condensation where as others do not have α – H atoms and they undergo cannizaro reactions.

Samacheer Kalvi 12th Chemistry Carbonyl Compounds and Carboxylic Acids 2 Mark Questions and Answers

Question 1.
Write the name of the following compounds.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-99

Question 2.
What happens But – 2 – ene is ozonised followed by hydrolysis?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-100

Question 3.
Explain the action of ozone with 2 – methyl but – 2 – ene followed by hydrolysis with zinc?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-101

Question 4.
What happens when Ethyne is hydrolysed in the presence of HgSO4 and H2SO4?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-102

Question 5.
How would you convert prop – 1 – yne to propanone?
Answer:
Prop – 1- lyne on hydrolysis with HgSO4 and H2SO4 gives propanone as product.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-103

Question 6.
Explain about the dry distillation of Calcium ethanoate.
Calcium ethanoate on dry distillation gives propanone as product.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-104

Question 7.
Explain Rosenmund reduction.
Answer:
Aldehydes can be prepared by the hydrogenation of acid chloride, in the presence of palladium supported by Barium sulphate. This reaction is called Rosenmund reduction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-105
In the above reaction, BaSO4 act as a catalytic poison to palladium catalyst, so that aldehyde cannot be further reduced to alcohol.

Question 8.
Explain Stephen’s reaction.
Answer:
In Stephen’s reaction, alkyl cyanide are reduced using SnCl2 / HCI, imines arc formed which on hydrolysis gives corresponding aldehyde.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-106

Question 9.
Explain the action of Diisobutyl aluminium hydride (DIBAL – H) and H2O with hex – 4 – en nitrile.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-107

Question 10.
Explain about Cattermann – koch reaction.
Answer:
Benzene reacts with carbon monoxide and HCl in the presence of AlCl3 and CuCl to give Benzaldehyde. This reaction is known as Gattermann – Koch reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-108

Question 11.
How would you manufacture benzaldehyde from toluene?
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-109
This is the commercial method for the manufacture of Benzaldehyde.

Question 12.
Explain the action of dialkyl cadmium with acetyl chloride?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-110

Question 13.
Explain the nucleophilic addition of HCN with eth anal?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-111

Question 14.
Which reaction finds application in the separation and purification ofcarbonyl compound? Explain.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-112
The bisuiphite compound is water soluble and the solution is treated with minerai acid to regenerate the carbonyl compound. So the above reaction is used in the separation and purification of carbonyl compound.

Question 15.
Complete the following reactions.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-113

Question 16.
What Is Clemmensen reduction ? Explain it.
Answer:
Aldehyde and ketones when heated with zinc amalgam and concentrated hydrochloric acid give hydrocarbons. This reaction is known as Clemmensen reduction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-114

Question 17.
Complete the following reactions.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-115
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-116

Question 18.
Explain Wolf Kishner reduction with suitable example.
Answer:
Wolf Kishner reduction:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-117

Question 19.
How would you obtain chloroform from acetone?
Answer:
When acetone is treated with chlorine and alkali, chloroform is formed.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-118

Question 20.
What happen when alcoholic KCN reacts with Benzaldehyde? (or) explain Benzoin condensation.
Answer:
Benzaldehyde reacts with alcoholic KCN to form Benzoin.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-119

Question 21.
Explain about SchilT’s reagent test?
Answer:
Dilute solution of aldehyde when added to Schifl’s reagent (Rosaniline hydrochloride dissolved in water and its red colour decolourised by passing SO2) yields its red colour. This is known as Schiffs’ test for aldehyde. Ketones do not give this test. Acetone however gives a positive test but slowly.

Question 22.
What are used of Urotropine? Give its structure.
Answer:
This is the structure of Urotropme (Hexamethylene tetramine)
1. Urotropine is used as a medicine to treat urinary infection.

2. Nitration ofUrotropine under controlled condition gives an explosive RDX (Research and development explosive). It is also called cyclonite or cyclotri methylene trinitramine.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-120

Question 23.
Mention the uses of aromatic ketone.
Answer:

  1. Acetophenone has been used in perfumery arid as a hypnotic under the name hyphone.
  2. Benzophenone is used in perfumery and in the preparation of benzhydrol drop.

Question 24.
Write the structure and IUPAC name of the following compounds?

(i) Malonic acid

(ii) Succinic acid

(iii) Glutaric acid

(iv) Adipic acid

Answer:

Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-120

Question 25.
Starting from methyl magnesium iodide, how would you prepare acetic acid?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-123

Question 26.
Convert phenyl magnesium bromide into Benzoic acid?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-302

Question 27.
Explain the hydrolysis reaction of the following with equation?

  1. (CH3CO)2O
  2. (C6H5CO)2O

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-303

Question 28.
Explain the action of alkaline potassium permanganate with toluene?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-124

Question 29.
Lower aliphatic carboxylic acids are miscible with water but higher carboxylic acids are insoluble in water. Give reason. (or) Acetic acid is soluble in water but hexanoic acid in insoluble in water. Why?
Answer:
Aliphatic acids are miscible with water due to the formation of hydrogen bonds with water. Higher carboxylic acids are insoluble in water due to increased hydrophobic interaction of hydrocarbon part. Thats why acetic acid is soluble in water whereas hexanoic acid is insoluble in water.

Question 30.
What is Vinegar? How will you get glacial acetic acid?
Answer:

  1. Vinegar is 6 to 8% solution of acetic acid in water.
  2. Pure acetic acid is called glacial acetic acid. Because it forms ice like crystal when cooled.

When aqueous acetic acid is cooled at 289.5 K, acetic acid solidifies and forms ice like crystals, where as water remains in liquid state and removed by filtration. This process is repeated to obtain glacial acetic acid.

Question 31.
Explain the action of the following reagents with acetic acid.

(i) PCI5

(ii) SOCI2

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-125

Question 32.
Complete the following reactions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-126
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-127

Question 33.
What happens when thionyl chloride reacts with benzoic acid?
Answer:
When Benzoic acid reacts with thionyl chloride, Benzoyl chloride is formed as product.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-128

Question 34.
Explain Kolbe’s electrolytic decarboxylation.
Answer:
The aqueous solution of sodium or potassium salts of carboxylic acid on electrolysis gives alkanes at anode. This reaction is called kolbe’s electrolysis.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-129

Question 35.
What happens when ammonia reacts with acetic acid?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-130

Question 36.
Explain the action of heat on acetic acid in the presence of phosphorous pentoxide.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-131

Question 37.
Explain the a – halogenation take place in acetic acid. (or) Explain IIell-Volhard-zelinsky reaction (HVZ reaction)?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-132
Carboxylic acids having an α – hydrogen are halogenated at the α – position on treatment with chlorine or bromine in the presence of small amount of red phosphorus to form a – halo carboxylic acids. This reaction is known as Hell – Volhard – Zelinsky reaction (HVZ reaction)

Question 38.
Acidity increases with increasing number of electron rithdrawing substituents on the α – carbon. Explain with example.
Answer:
Acidity increases with increasing number of electron withdrawing substituents on the α – carbon atom. For example,
Cl3C – COOH > Cl2CH – COOH > Cl – CH2COOH > CH3COOH
The effect of various, electron withdrawing groups on the acidity of a carboxylic acid follows the order,
– NO2 > – CN > – F > – Cl > – Br > – I > Ph

Question 39.
Trichloro acetic acid is more acidic than acetic acid. Give reason.
Answer:
Cl is an electron withdrawing substituent. Acidity increases with the increasing number of electron withdrawing substituents on the α – carbon. So trichioro acetic acid is more acidic than acetic acid. CCI3COOH is more acidic than CH3COOH.

Question 40.
Fluoro acetic acid is more acidic than iodoacetic acid. Give reason.
Answer:
Acidity increases with increasing electro negativity of the substituents. F is more electro negative.
F – CH2 – COOH > Cl – CH2COOH > Br – CH2 – COOH > 1 – CH2 – COOH
So Fluoro acetic acid is more acidic than iodoacetic acid.

Question 41.
What are carboxylic acid derivatives? Give four examples.
Answer:
1. Carboxylic acid derivatives are compounds in which carboxylic acid – OH group is replaced by the atom or the group.

2. Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-133

Question 42.
Which is the best method to prepare acetyl chloride from acetic acid? why?
Answer:
Acetyl chloride is prepared from acetic acid by the action of thionyl chloride. This method is superior to others as the by products being gases escape leaving the acid chloride in the pure state.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-134

Question 43.
Acetyl chloride fumes when exposed to air. Give reason.
Answer:
Acetyl chloride emit pale fumes of hydrogen chloride when exposed to air on account of their reaction with water vapour.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-135

Question 44.
What happens when acetyl chloride is treated with ethanol?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-136
This reaction is also known as alcoholysis.

Question 45.
Explain ammonolysis reaction of acid chloride (or) what happens when ammonia reacts with acetvl chloride?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-137

Question 46.
What happens when acetic anhydride reacts with ethyl alcohol?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-138

Question 47.
Explain the reaction of ammonia with acetic anhydride.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-139

Question 48.
Complete the following reaction.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-140
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-141

Question 49.
What is transesterification? Explain with example.
Answer:
Esters of an alcohol can react with atiother alcohol in the presence of a mineral acid to give the ester of second alcohol. The interchange of alcohol portions of the esters is termed transesterification.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-142

Question 50.
Explain the action of ammonia with ethyl acetate.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-142

Question 51.
How is ethyl acetate react with PCL5?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-143

Question 52.
What happens when methyl cyanide is partially hydrolysed by cold conc. HCl?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-144

Question 53.
Explain the action of P2O5 with acetamide with equation.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-145

Question 54.
Describe Hoffmann degradation reaction. (or) How would you obtain methyl amine from acetamide?
Answer:
Acetamide reacts with bromine in the presence of caustic alkali to form a primary amine carrying one carbon less than the parent amide.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-48

Question 55.
How would you preparate ethyl amine from acetamide?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-147

Question 56.
What are the used of acetyl chloride?
Answer:

  1. Acetyl chloride is used as acetylating agent in organic analysis
  2. it is used in the detection and estimation of – OH, – NH2 groups in organic compounds.

Question 57.
Arrange the following compounds ¡n increasing order of their reactivity in nucleophilic addition reactions.

  1. Ethanal, Propanal, Propanone, Butanone
  2. Benzaldehyde, p – Tolualdehyde, p – Nitrobenzaldehyde, Acetophenone

Answer:

  1. Butanone < Propanone < Propanal <Ethanal
  2. Acetophenone < p – Tolualdehyde < Benzaldehyde < p – Nitrobenzaldehyde

Question 58.
Give the IUPAC names of the following compounds:

(i) PhCH2CH2COOH

(ii) (CH3)2C = CHCOOH

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-148

  1. 3 – Phenylpropanoic acid
  2. 3 methylbut – 2 – enoje acid
  3. 2 – methylcyclohexane carboxylic acid
  4. 2, 4, 6 – Trinitorbenzoic acid or 2, 4, 6, – Trinitrobenzene carboxylic acid

Question 59.
Although phenoxide ion has more number of resonating structures than carboxylate ion, carboxylic acid is a stronger acid than phenol? Why?
Answer:
In carboxylate ion -ve charge is delocalised over two oxygen atoms whereas in phenoxide ion the -ve charge is delocalised over one oxygen atom. Therefore carboxylate ion is more stable than phenoxide ion and that is why carboxylic acids are more acidic than phenols.

Question 60.
How is aminoethane obtained from ethanal (acetaldehyde)?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-304

Question 61.
Why HCOOH does not give Hell – Voihard Zelinsky reaction but CH3COOH does?
Answer:
CH3COOH contains α – hydrogen atom and hence gives HVZ reaction but HCOOH does not contain an α – hydrogen atom and hence does not give HVZ reaction.

Question 62.
Write IUPAC names of the following.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-149
Answer:

  1. 3 – Methylpent – 2 – 3n 3 – 1, 5 – dioic acid
  2. 6 – Bromo -3 – hydroxy- 5 – nitrobenzoic acid

Question 63.
Give chemical tests to distinguish between the following pair of compounds.

  1. Phenol and Benzoic acid
  2. Benzaldehyde and Acetophenone

Answer:

  1. By adding feme chloride, phenol will give violet colour whereas benzoic acid will not react.
  2. Adding I2 and NaOH, Acetophenone will give yellow ppt. of iodoform whereas benzaldehyde will not react.

Question 64.
Give chemical tests to distinguish between the following pair of compounds.

  1. Propanoyl chloride and propanoic acid
  2. Benzaldehyde and Acetophenone

Answer:
1. On adding NaHCO3, solution to each of them, propanoyl chloride will not react whereas propanoic acid will give brisk èfferevescence due to the evolution of CO2.

2. On adding I2 and NaOH, Acetophenone will give yellow ppt, of iodoform whereas benzaldehyde will not react

Question 65.
Give chemical tests to distinguish between the following pair of compounds.

  1. Propanal and propanone
  2. Benzaldehyde and Benzoic acid

Answer:

  1. On adding Tollen’s reagent, propanal will give silver mirror whereas propanone does not react.
  2. On adding NaHCO3 solution, benzaldehyde will not react whereas benzoic acid will give brisk effervescence due to the evolution of CO2.

Question 66.
Out of acetophenone and benzophenone, which one will give iodoform test? Write the reaction involved. (The compound should have CH3CO group to show the iodoform test).
Answer:
Acetophenone (C6H5COCH3) contains the group (CH3CO) attached to the carbon atom and hence give lodoform test while benzophenone does not contain this group and hence does not give iodoform test.

Question 67.
Why does methanal not give aidol condensation while ethanol forms an aldol?
Answer:
This is because only those compounds which haie α – hydrogen atoms can undergo aldol condensation reactions. Ethanol possesses α – hydrogen and therefore undergoes aldol condensation. Methanal does not have α – hydrogen atoms, hence does not undergo aldol condensation reactions.

Samacheer Kalvi 12th Chemistry Carbonyl Compounds and Carboxylic Acids 3 Mark Questions and Answers.

Question 1.
Draw the structure and IUPAC name of the following compounds.

(i) Acrolein

(ii) Crotonaldehyde

(iii) Glyceraldehyde

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-209

Question 2.
Draw the structure and IUPAC name of the following compounds.

(i)  Mesityl oxide

(ii) Acetophenone

(iii) Benzophenone

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-210

Question 3.
Explain about the structure of carbonyl group.
Answer:
1. The carbonyl carbon

is sp2 hybridised and carbon – oxygen bond is similar to carbon carbon double bond in alkenes. The carbonyl carbon forms three o bonds using their three sp2 hybridised orbital. One of the sigma bond is formed with oxygen and the other two with hydrogen and carbon (in aldehydes) or with two carbons (in ketones). All the three ‘a’ bonded atoms arc lying on the same plane.

2. The fourth valence electron of carbon remains in its unhybridised ‘2p’ orbital which lies perpendicular to the plane and it overlaps with 2p orbital of oxygen to form a carbon – oxygen bond.

3. The oxygen atom has two non-bonding pairs of electrons, which occupy its remaining two P orbitais. Oxygen, the second most electro negative atom attracts the shaired pair of electron between the carbon and oxygen towards itself and hence the bond is polar. This polarisation contributes to the reactivity of aldehydes and ketones.

Question 4.
How are the following compounds are prepared by the dry distillation of calcium salt of carboxylic acids?

(i) Methanal

(ii) Ethanal

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-211

Question 5.
How will you prepare benzaldehyde from methyl benzene? (or) Explain Etard reaction.
Answer:
When chromylchloridc is used as an oxidising agent, toluene gives benzaldehyde. This reaction is called Etard reaction. Acetic anhydride and CrO3 can also be used for this reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-212

Question 6.
How would you prepare the following compounds by Friedel Crafts acylation?

(i) Acetophenone

(ii) Benzophenone

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-213

Question 7.
Aldehydes and ketones have high boiling point as compared to hydrocarbons and ethers of comparable molecular mass and less than that of alcohols. Give reason.
Answer:
Aldehydes and ketones have high boiling point as compared to hydrocarbons and ethers of comparable molecular mass. It is due to the weak molecular association in aldehyde and ketone arising out of the dipole-dipole interactions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-214
These dipole – dipole interactions are weaker than intermolecular H – bonding. The boiling points of aldehydes and ketones are much lower than those of corresponding alcohols and carboxylic acids which possess inter molecular hydrogen bonding.

Question 8.
Explain the mechanism of nucleophilic addition reactions of aldehyde and ketone?
Answer:
1. Nucleophilic addition reaction is the most common reactions of aldehydes and ketones. The carbonyl carbon cames a small degree of positive charge.

2. Nucleophile such as CN can attack the carbonyl carbon and uses its bond pair to forni a new carbon – nucleophile’ a ‘bond, at the same time two electrons from the carbon – oxygen double bond move to the most electronegative oxygen atom.

3. This results in the formation of an alkoxide ion. In this process, the hybridisation of carbon changes from sp2 to sp3
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-215
The tetrahedral intermediate can be protonated by water or an acid to form an alcohol.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-216

Question 9.
How acetone reacts with the following reagents?

(i) NH2OH

(ii) NH2 – NH2

(iii) C6H5NH – NH2

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-217

Question 10.
What is Urotropine? How is It prepared? Mention Its structure and uses.
Answer:
1. Urotropine is hexamethylene tetramine. N

2. Formaldehyde reacts with ammonia to form hexamethylene tetramine, which is called Urotropine. HC CH1 CH
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-218

3. Urotropine is used as a medicine to treat urinary infection.

4. Nitration of Urotropine under controlled condition gives an explosive RDX (Research and development explosive). It is also called cyclonite or cyclotri methylene trinitramine.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-219

Question 11.
What is popoff ‘s rule? Explain with an example.
Answer:
The oxidation of unsymmetrical ketones is governed by Popoff’s rule. It states that during the oxidation of an unsymmetrical ketone, a (C – CO) bond is cleaved in such a way that the keto group stays with the smaller alkyl group. Example:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-220

Question 12.
Explain the action of magnesium amalgam and water with acetone?
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-221

Question 13.
Describe crossed aldol condensation with two examples.
Answer:
Aldol condensation can takes place between two different aldehyde or ketones or between one aldehyde and one ketone is called crossed or mixed aldol condensation. E.g.,
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-222

Question 14.
Explain Claisen – Schmidt condensation.
Answer:
Benzaldehye condenses with acetaldehyde or acetone in the presence of dil. alkali at room temperature to form unsaturated aldehyde (or) ketone. This type of reaction is called Claisen – Schmidt condensation.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-223

Question 15.
What is crossed cannizaro reaction? Explain It.
Answer:
When Cannizaro reaction (Auto redox reaction) takes place between two different aldehyde, the reaction is called as crossed cannizaro reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-224
In crossed cannizaro reaction more reactive aldehyde is oxidized and less reactive aldehyde is reduced.

Question 16.
How will you prepare malachite green dye from Benzaldehyde?
Answer:
Benzaldehyde condenses with tertiary aromatic amines like N, N – dimethyl aniline in the presence of strong acids to triphenyl methane dye.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-225

Question 17.
How Is chlorine react with Benzaldehyde?

 

  • In the presence of catalyst
  • In the absence of catalyst

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-226

Question 18.
Explain about 3 test for aldehyde
Answer:
1. Tollen’s reagent test:
When an aldehyde is warmed with Tollens reagent(Ammonical silver nitrate), a bright silver mirror is produced due to the formation of silver metal. This reaction is also called silver mirror test for aldehydes.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-227

2. Fehlings solution Test:
Fehlings solution is prepared by mixing equal volumes of Fehlings solution ‘A’ containing aqueous copper sulphate and Fehlings solution ‘B’ containing alkaline solution of sodium potassium tartarate (RocheLle salt) When aldehyde is warmed with Fehlings solution deep blue colour solution is changed to red precipitate of cuprous oxide.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-228

3. Benedict’s solution Test:
Benedict’s solution is a mixture of CuSO4 + sodium citrate + NaOH. Cu2+ is reduced by aldehyde to give red precipitate of cuprous oxide.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-229

Question 19.
Mention the uses of formaldehyde.
Answer:

  1.   40% aqueous solution of formaldehyde is called formalin. It is used for preserving biological specimens.
  2. Formalin has hardening effect, hence it is used for tanning.
  3. Formalin is used in the production of thermo setting plastic known as bakelite, which is obtained by heating phenol with formalin.

Question 20.
What are the uses of acetaldehyde?
Answer:

  1. Acetaldehyde is used for silvering of mirrors
  2. Paraldehyde is used in medicine as a hypnotic.
  3. Acetaldehyde is used in the commercial preparation of organic compounds like acetic acid, ethyl acetate etc.,

Question 21.
Write about the uses of Acetone.
Answer:

  1. Acetone is used as a solvent, in the manufacture of smokeless powder (cordite)
  2. It is used as a nail polish remover.
  3. It is used in the preparation of suiphonal, a hypnotic.
  4. It is used in the manufacture of thermosoftening plastic Perspex.

Question 22.
What are the uses of Benzaldehyde?
Answer:

  1. as a flavoring agent
  2. in perfumes
  3. in dye intermediates
  4. as starting material for the synthesis of several other organic compounds like cinnamaldehyde, cinnamic acid, benzoyl chloride etc.

Question 23.
Carboxylic acids have higher boiling pint than aldehyde, keton and even alcohols of comparable molecular masses. Give reason.
Answer:
Carboxylic acids have higher boiling point due to more association of acid molecules through inter molecular hydrogen bonding.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-230
In fact, most of the carboxylic acids exist as dimer in its vapour phase.

Question 24.
What happens when ethanoic acid reacts with the following reagents?

  1. LiAIH4
  2. Red P, Hl

Answer:
1. When ethanoic acid reacts by LiAIH4, partial reduction take place and ethanol is formed as a product.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-231

2. When ethanoic acid is treated with HI and red phosphorous, complete reduction take place and alkane is formed as a product.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-232

Question 25.
Explain the action of sodalime with sodium acetate. Name the type of reaction involved in ¡t.
Answer:
When sodium acetate is treated with sodalime, methane is formed.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-233
Removal of CO2 from carboxyl group take place in it and this is called decarboxylation

Question 26.
Explain about electrophilic substitution in Benzoic acid with example.
Answer:
Benzoic acid undergoes electrophilic substitution. The carboxyl group is a deactivating and meta directing group.
1. Halogenation.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-234

2. Nitration
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-235

3. Sulphonation
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-236

Quesiton 27.
Formic acid act as reducing agent. Prove this statement.
Answer:
1. Formic acid contains both an aldehyde as well as an acid group. Hence, like other aldehydes, formic acid can easily be oxidised and therefore acts as a strong reducing agent.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-237

2. Formic acid reduces Tollen’s reagent (ammonical silver nitrate solution) to metallic silver.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-238

3. Formic acid reduces Fehling’s solution. It reduces blue coloured cupric ions to red coloured cuprous ions.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-239

Question 28.
Give three test for carboxylic acid.
Answer:

  1. In aqueous solution, carboxylic acid turn blue litmus red.
  2. Carboxylic acids give brisk effervescence with. sodium bicarbonate due to the evolution of carbon – di – oxide.
  3. When carboxylic acid is warmed with alcohol and conc H2SO4 it forms an ester, which is detected by its fruity odour.

Question 29.
Write a note about acidity of carboxylic acids.
Answer:
1. Carboxylic acids undergo ionisation to produce W and carboxylate ions in aqueous solution. The carboxylate ion is stabilised by resonance which make the Carboxylic acid to donate the proton easily.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-240

2. The resonance structure of carboxylate ion are given below.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-241

3. The strength of carboxylic acid can be expressed in terms of the dissociation constant(Ka):
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-242
The stronger the acid, the large will be its Ka value.
PKa = – log Ka
A strong acid will have higher ka value but smaller pKa value, the reverse is true for weak acid.

Question 30.
Formic acid is more stronger than acetic acid. Justify this statement. The electron releasing groups (+I groups) increase the relative charge on the carboxylate ion and destabilise it and hence the loss of proton becomes difficult.
+ I groups are CH3, – C2H5, – C3H7
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-243

Question 31.
Explain the order of relative reactivity of acid derivatives.
Answer:
1. The reactivity of the acid derivatives follows the order
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-244

2. The above order of reactivity can be explained in terms of
Basicity of the leaving group
(b) Resonance effect

3. Weaker bases are good leaving groups. Hence acyl derivatives with weaker bases as leaving groups (L) can easily rupture the bond and are more reactive. The correct order of the basicity of the leaving group is
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-245
Hence the reverse is the order of reactivity.

4. Lesser the electronegativity of the group, greater would be the resonance stabilization as shown below.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-246
This effect makes the molecule more stable and reduces the reactivity of the acyl compound. The order of electronegativity of the leaving groups follows the order – Cl > – OCOR > – OR > – NH2. Hence the order of reactivity of the acid derivatives with nucleophilic reagent follows the order
Acid halide > Acid anhydride> esters> Acid amides

Question 32.
Explain the following reaction with acetyl chloride

  1. ammonolysis.

Answer:
Reaction with ammonia is known as arninonolysis
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-247

Question 33.
Explain the action of the following reagents with acetyl chloride?

  1. Pd / BaSO4
  2. LiAIH4

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-248

Question 34.
Describe about Claisen condensation.
Answer:
Esters containing at least one α – hydrogen atom undergo self condensation in the presence of a strong base such as sodium ethoxide to form β – keto ester. This reaction is known as Claisen condensation.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-249

Question 35.
Acid amides are generally amphoteric in nature. Justify this statement.
Answer:
1. Amides behave both as weak acid as well as weak base and thus show amphoteric character. This can be proved by the following reactions.

2. Acetamide (as base) reacts with hydrochloric acid to form salt
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-250

3. Acetamide (as acid) reacts with sodium to form sodium salt and hydrogen gas is liberated
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-251

Question 36.
Mention the uses of formic acid?
Answer:
Formic acid. It is used

  1. for the dehydration of hides.
  2. as a coagulating agent for rubber latex
  3. in medicine for treatment of gout
  4. as an antiseptic in the preservation of fruit juice

Question 37.
What are the uses of acetic acid?
Answer:
Acetic acid is used

  1. as table vinegar
  2. for coagulating rubber latex
  3. for manufacture of cellulose acetate and poiy vinylacetate

Question 38.
Indicate the uses of Benzoic acid.
Answer:
Benzoic acid is used

  1. as food preservative either in the pure form or in the form of sodium benzoate
  2. in medicine as an urinary antiseptic
  3. for manufacture of dyes

Question 39.
What are the uses of acetic anhydride?
Answer:
Acetic anhydride is used

  1. acetylating agent
  2. in the preparation of medicine like aspnn and phenacetin
  3. for the manufacture plastics like cellulose acetate and poly vinyl acetate.

Question 40.
Mention the uses of Ethyl acetate?
Answer:
Ethyl acetate is used

  1. in the preparation of artificial fruit essences.
  2. as a solvent for lacquers.
  3. in the preparation of organic synthetic reagent like ethyl acetoacetate.

Question 41.
Give reasons for the following.

  1. Carboxylic acids do not give characteristic reactions of carboxyl group
  2. Treatment of benzaldehyde with HCN gives a mixture of two isomers which cannot be separated even by careful fractional distillation.
  3. Sodium bisuiphite is used for the purification of aldehydes and ketones.

Answer:
1. It is due to reasonance
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-252

2. It is because we get two optical isomers which have same physical properties, therefore, cannot be separated by fractional distillation.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-253

3. Aldehydes and ketones form addition compounds with NaHSO3 whereas any impurities do not. On hydrolysis, we get pure aldehydes and ketones back again.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-254

Question 42.

(i) Describe the preparation of acetic acid from acetylene.

(ii) How can the following be obtained from acetic acid:

(a) Acetone

(b) Acetaldehyde

(iii) In what way can acetic acid be distinguished from acetone?

(iv) Why carboxylic acid do not give the characteristic reactions of a carbonyl group?

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-255

(iii). Add I2 and NaOH. Acetone will give yellow precipitate of iodoform whereas acetic acid does not react to give any yellow precipitate.(or) Add sodium bicarbonate solution Acetone will not react, but acetic acid will give brisk effervescence due to the evolution of CO2.

(iv). Carboxylic acid does not give the characteristic reactions of carbonyl group due to reasonance effect by the virtue of which it does not have free
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-256
carbonyl group.

Question 43.
Account for the following

  1. Cl – CH2COOH is a stronger acid than CH3COOH
  2. Carboxylic acids do not give reactions of carbonyl group.

Answer:
1. MonochLoroacetic acid is comparatively stronger acid than acetic acid. This is due to – Cl as a – I group

2. Carboxylic acids do not give reactions of carbonyl group because the lone pair of electrons on the oxygen attached to hydrogen in the – COOH group are involved in resonance, which makes the carbon less electrophilic.

Question 44.
A group of students were given to study the properties of aldehydes and ketones in the lab. They recorded a few observation of their physical properties.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-257

  1. Why are aldehydes more reactive and moreioiuble than ketones?
  2. What values of students are seen from the above act?

Answer:

  1. Aldehydes are more soluble in water because they form hydrogen bond with water molecule.
  2. Critical thinking

Question 45.
How will you distinguish between methanol and ethanol?
Answer:
By Iodoform test:
Ethanol having α – methyl group will give yellow ppt of iodoform whereas methanol, which do not have α – methyl group, will not give ppt. of iodoform.

Question 46.
There are two – NH2 group in semicarbazide. However, only one is involved in the formation of semicarbazone. Why?
Answer:
Although semicarbazide has two – NH2 groups but only one of them is involved in resonance as shown below.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-258
As a result, e density on one of the – NH2 group is reduced and hence it does not act as nucleophile. One pair of the other – NH2 group is not involved in resonance and hence it is available for nucleophilic attack.

Question 47.
Explain why o – hydroxybenzaldehyde is a liquid at room temperature while p – hydroxybenzaldehyde is a high melting solid?
Answer:
Due to intramolecular H – bonding orthohydroxy benzaldehyde exists as discrete molecule whereas due to intermolecular H – bonding, p – hydroxybenzaldehyde exists as associated molecules. To break these intermolecular H – bonds, a large amount of energy is needed.

Consequently, p – hydroxybenzaldehyde has a much higher m.pt. and b.pt. than that of o – hydroxy benzaldehyde. As a result, o -hydroxy benzaldehyde is a liquid at room temperature while p – hydroxy benzaldehyde is a high melting solid.

Question 48.
A compound ‘X’ (C2H4O) on oxidation gives ‘Y’ (C2H4O2), ‘X’ undergoes haloform reaction. On treatment with HCN ‘X’ form a product ‘Z’ which on hydrolysis gives 2 – hydroxy propanoic acid.

  1. Write down the structures of ‘X’ and ‘Y’
  2. Name the product when ‘X’ reacts with dii NaOH.
  3. Write down the equations for the reaction involved.

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-259
Structure of Y (CH3COOH)
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-260

Question 49.

1. How will you prepare

  • Acetic anhydride and
  • Acetyl chloride from acetic acid?

Write the reactions involved in each case.
2. Why is the boiling point of an acid anhydride higher than the acid from which it is derived?
Answer:
1.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-261

2. Acid anhydrides are bigger sized molecules than the corresponding acids, therefore have more surface area, more van der Waals’ forces of attraction and hence higher boiling points.

Question 50.
Suggest a reason for the large difference in the boiling point of butanol and butanal, although they have the same solubility in water.
Answer:
The b.pt. of butanol is higher than that of butanal because butanol has strong intermolecular H – bonding while butanal has weak dipole – dipole interactions. However both of them will form H – bond with water and hence are soluble.

Samacheer Kalvi 12th Chemistry Carbonyl Compounds and Carboxylic Acids 5 Mark Questions and Answers

Answer the following questions.

Question 1.
Explain the action of ammonia with the following compounds.

Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-262

Answer:
(i).  Formaldehyde reacts with ammonia to form hexa methylene tetramine, which is also known as UrotroDine.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-263

Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-264

Question 2.
Explain the mechanism of aldol condensation.
Answer:
In presence of dilute base NaOH, or KOH, two molecules of an aldehyde or ketone having α – hydrogen add together to give 3 – hydroxyl aldehyde (aldol) or – hydroxyl ketone (ketol). The reaction is called aldol condensation reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-265
Mechanism
The mechanism of aldol condensation of acetaldehyde takes place in three steps.
Step 1:
The carbanion is formed as the α – hydrogen atom is removed as a proton by the base.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-266

Step 2:
The carbanion attacks the carbonyl carbon of another unionized aldehyde to form an alkoxide ion.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-267

Step 3:
The alkoxide ion formed is protonated by water to form aldol.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-268
The aldol rapidly undergoes dehydration on heating with acid to form a, f3 unsaturated aldehyde.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-269

Question 3.
Explain the mechanism of Cannizaro reaction.
Answer:
1. In the presence of concentrated aqueous or alcoholic alkali, aldehydes which do not have α – hydrogen atom undergo self oxidation and reduction to give a mixture of alcohol and a salt of carboxylic acid. This reaction is called Cannizaro reaction.

2. Benzaldehyde on treatment with concentrated NaOH (50%) gives benzyl alcohol and sodium benzoate.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-270

Mechanism
Cannizaro reaction involves three steps.
3. Step 1:
Attack of OH on the carbonyl carbons.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-271

4. Step 2:
Hydride ion transfer
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-272

5. Step 3:
Acid – base reaction
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-273

Question 4.
Explain

  1. Perkin’s reaction
  2. Knocvenagal reaction.

Answer:
1. Perkin’s reaction
When an aromatic aldehyde is heated with an aliphatic acid anhydride in the presence of the sodium salt of the acid corresponding to the anhydride, condensation takes place and an α, β unsaturated acid is obtained. This reaction is known as Perkin’s reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-274

2. Knoevenagal reaction
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-275

Question 5.
Explain about electrophilic substitution reactions of Benzaldehyde and acetophenone.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-276

Question 6.
How would you prepare acetic acid from the following compounds.

  1. Ethyl alcohol
  2. Methyl cyanide
  3. Ethyl acetate

Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-277

Question 7.
What is esterification? Explain the mechanism of esterification.
Answer:
When carboxylic acids are heated with alcohols in the presence of conc. HCI (or) dry HCI gas, esters are formed. This reaction is reversible and is called esterification.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-278

Question 8.
An organic compound (A) (molecular formula C8H16O2) was hydrolysed with dilute sulphuric acid to give a carboxylic acid (B) and an alcohol (C). Oxidation of (C) with chromic acid produced (B). (C) on dehydration gives but -1-ene. Write equations for the reactions involved.
Answer:
The relevant equations for all the reactions involved may be explained as follows.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-279

Question 9.
An organic compound (A) of molecular formula CH6 reacts with Br2 in the presence of FeCI3 gives (B) of formula C6HBr. B on treatment with mg in the presence of dry ether gives (C) compound (C) on treatment with dry ice followed by hydrolysis gives a compound (D) of molecular formula C7H6O2. Identify A,B,C,D and explain the reactions involved.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-280

Question 10.
A simplest aromatic hydrocarbon (A) reacts with methyl chloride in the presence of AICI3 gives (B) C7H8. Compound (B) reacts with Br2 along with light gives (C) of molecular formula C7H7Br (C) reacts with alcohol KCN gives (D) (C8H7N) (D) on acid hydrolysis gives (E) of formula C8H8O2. Identify A,B,C,D,E and explain the reactions involved.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-281

Question 11.
An organic compound (A) is a calcium salt of acetic acid. (A) on dry distillation gives (B) of formula C3H6O. (B) on reaction with LiAIH4 gives (C) of formula C3H8O (C) on heating with conc. H2SO4 gives (D) of molecular formula C3H6. Identify A,B,C,D and explain the reaction involved.
Answer:

Question 12.
An organic compound (A) of molecular formula C7H8O on oxidation with alkaline KMnO4 gives (B) of formula C7H6O. (B) on reaction with CI2 in the presence of catalyst FeCl3 gives (C) of formula C7HOCl. (B) on reaction with CI2 in the absence of catalyst gives C7H5OCI. Identify A,B, C,D and explain the reaction involved.
Answer:
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-282

Question 13.
An organic compound (A) of molecular formula C7H6O reacts with acedaldehyde In the presence of sodium ethoxide gives (B) of formula C9H8O an unsaturated aldehyde. Compound (A) reacts with acetic anhydride in the presence of sodium acetate gives (C) and (D) of formula C9HO2 & C2H4O2 respectively. Identify AB,C,D and explain the reaction involved.
Answer:
1. From the molecular formula (A) is identified as Benzaldehyde C6H5CHO.Benzaldehyde reacts with acetaldehyde to give cinnamaldehyde as B in Claisen condensation reaction.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-283

2. Benzaldehyde reacts with acetic anhydride (Oerkin’s reaction) to give cinnamic acid (C) as product.
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-284

Question 14.
An aromatic aldehyde (A) of molecular C7H6O reacts with acidified KMnO4 to give (B) of molecular formula C7H6O2 calcium salt of compound (B) on dry distillation gives (C) of molecular formula C13H10O Compound (C) on Clemmenson’s reduction, gives (D) of formula C13H12O. Identify A,B,C,D and explain the reaction involved.
Answer:
1. From the molecular formula (A) is identified as Benzaldehyde C6H5CHO.Benzaldehyde on reaction with acidified KMnO4 undergoes oxidation to give Bcnzoic acid as compound (B)
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-285

2. Calcium salt of Benzoic acid on dry distillaiton gives Benzophenone as compound (C)
Samacheer Kalvi 12th Chemistry Solutions Chapter 12 Carbonyl Compounds and Carboxylic Acids-286

3. Benzophenone undergoes Clemmenson reduction in the presence Zn amalgam and HCI gives Diphenyl methane as (D)

Question 15.
A simplest aromatic hydrocarbon (A) of formula C6H6 reacts with Bromine to gives (B) of molecular formula C6H5Br. (B) on treatment with magnesium metal in the presence of dry ether gives (C) . (C) on reaction with formaldehyde followed by acid hydrolysis gives (D) of formula C7H8O. Identify AB,C,D and explain the reaction involved.
Answer:
1. From the molecular formula (A) is identified as Benzene C6H6, Benzene reacts with Bromine to give bromobenzene as (B)

2. Bromobenzene reacts with Mg in the presence of dry ether gives phenyÍ magnesium bromide (Grignard reagent) as compound (C)

3. Phenyl magnesium bromide react with formaldehyde followed by acid hydrolysis gives Benzyl alcohol as product (D)

Question 16.
An organic compound (A) of molecular formula C2H3N on acid hydrolysis gives (B) of molecular formula C2H4O2 calcium salt of (B) gives (C) of molecular formula C3H6O. Compound (C) on reduction of hydrazine and sodium ethoxide gives (D) of molecular formula C3H8. Identify A,B,C,D and explain the reaction involved.
Answer:
1.
2.
3. Wolf – Kishner reduction

Question 17.
An organic compound (A) of molecular formula C7H8 on reaction with hot alkaline KMnO4 gives (B) of formula C7H6O2 which gives brisk effervescence with NaHCO3 solution. (B) on reaction with sodium hydroxide gives (C) of formula C7H5O2Na. Compound (C) on treatment with sodalime gives (D) the simplest aromatic hydrocarbon.
Answer:
1. From the molecular formula (A) is identified as Toluene. Toluene on treatment with hot alkaline KMnO4, oxidation take place and the product (B) formed is Benzoic acid.

2. Benzoic acid reacts with sodium hydroxide to give sodium benzoate as compound (C)

3. Sodium benzoate on reaction with sodalime (NaOH + CaO) decarboxylation take place and the product (D) formed is Benzene.

Question 18.
An organic compound (A) molecular formula C3H6O is resistant to oxidation but form a compound (B) (C3H8O) on reduction (B) reacts with HBr to form a bromide (C) which on treatment with alcoholic KOH forms an alkene (D) (C3H6). Deduce the structures of A,B,C and D.
Answer:

Question 19.
An organic compound (A) of molecular formula C6H6O gives violet colour with neutral FeCI3. (A) on reaction with zinc dust gives (B) of formula C6H6 (B) on treatment with acetvl chloride in the presence of anhydrous AICI3 gives (C) of formula C8HO. (C) on Clemmenson reduction gives (D) of formula C8H10O. Identify A,B,C,D and explain the reaction involved.
Answer:

Question 20.
An organic compound (A) of molecular formula C3H6O reduces Tollen’s reagent on reaction with methyl magnesium bromide followed by acid hydrolysis gives (B) of formula C4H10O. (B) gives blue colour in victor meyer test. (B) on reaction with Cu at 573 K gives (C) of formula C4H8O (C) on reaction with hydrazine and sodium ethoxide gives (D) of molecular formula C4H10. identify A,B,C,D and explain the reactions involved.
Answer:
1. An organic compound (A) reduces Tollen’s reagent it must be an aldehyde. From the formula, it is identified as CH3 – CH2 – CHO propanal.

2. Propanal on reaction with methyl magnesium bromide followed by acid hydrolysis gives (B) as Butan – 2 – ol. It must be a secondary alcohol and gives blue colour with victor meyer’s test. H

3.

4. Wolf – Kishner reduction.

Question 21.
An organic compound (A) of molecular formula C7H6O2 reacts with PCI5 to give (B) of formula C7H5OCl (B) on treatment with ammonia gives (C) of formula C7H7NO (C) on treatment with phosphorous pentoxide gives (D) of formula C7H5N. Identify A,BC,D and explain the reactions involved.
Answer:

Question 22.
An organic compound (A) of molecular formula C3H6 on hydration in the presence of H2SO4 gives (B) C3H5O which gives blue colour In victor meyer’s test. (B) on treatment with Cu at 573 K gives C3H6O a compound (C) on self condensation in the presence of magnesium amalgam and water gives (D) of formula C6H14O2. Identify A,B,C,D and explain the reaction involved.
Answer:

Question 23.
An organic compound (A) of molecular formula C2H4O reduces tollen’s reagent to silver mirror. (A) on treatment with C2H5MgBr followed by acid hydrolysis gives (B) of formula C4H10O. (B) on reaction with Cu at 573 K gives (C) of formula C4H8O which does not reduce tollen’s reagent but answers iodoform test. Identify A,B,C,D and explain the reaction involved.
Answer:

Question 24.
An unknown aldehyde ‘A’ on reacting with alkali gives a b – hydroxy – aldehyde, which loses water to form an unsaturated aldehyde, 2 – butenal. Another aldehyde ‘B’ undergoes disporportionation reaction in the presence of conc. alkali to form products C and D. C is – an aryl alcohol with formula C7H8O.

  1. Identify A and B.
  2. Write the sequence of reactions involved
  3. Name the product, when ‘B’ reacts with Zn amalgam and hydrochloric acid.

Answer:

1. ‘A’ is acetaldehyde ‘B’ is Benzaldehyde

2. reactuib are shown above.

Question 25.
An organic compound (A) of molecular formula C4H8 is symmetric alkene. (A) on ozonolysis gives 2 moles (B) of molecular formula C2H4O. (B) on reaction with ammonia gives (C) of molecular formula C2H5N.
Answer:
1. (A) is a symmetric alkene. From the molecular formula, it is identified as But – 2 – ene

2. But – 2 – ene on ozonolysis gives 2 moles of acetaldehyde as product (B)

3.

Question 26.
An organic compound (A) of molecular formula C2H4O2 gives brisk effervescence with sodium carbonate. (A) on reaction with thiony chloride gives (B) of formula C2H3OCI. (B) on reaction with Pd/BaSO4 gives (C) of molecular formula C2H4O that reduces Tollen’s reagent to silver mirror. (C) on reaction with dilute NaOH gives (D) of molecular formula C4H8O2. identify A,B,C,D and explain the reactions involved.
Answer:
1. (A) gives brisk effervescence with Na2CO3 means it must be a carboxylic acid. So (A) must be CH3COOH Acetic acid.

2. Acetic acid reacts with thionyl chloride to give acetyl chloride CH3COCI as (B)

3. Acetyl chloride reacts with Pd/BaSO4, it undergoes Rosenmund’s reduction to give acetaldehyde as (C)

4. When acetaldehyde is warmed with dilute NaOH, it undergoes aldol condensation to

Question 27.
An organic compound (A) of molecular formula C7H8 reacts with CI2 in the presence of ho light gives (B) of formula C7H6C12. (B) on hydrolysis at 373 k gives (C) of formula C7H6O. (C) on treatment with 50% NaOH gives (D) and (E). Identify A,B,CD,E and explain the reactions involved.
Answer:
1. From the molecular formula (A) is identified as Toluene. ToÍuene reacts with Cl2 in the presence of light gives Benzal chloride as (B)

2. Benzal chloride on hydrolysis at 373 k gives Benzaldehyde as (C)

3. Benzaldehyde when warmed with dilute NaOH undergoes cannizaro reaction to give Benzyl alcohol (D) and sodium benzoate (E)

Question 28.
An organic compound (A) of molecular formula C2H3OCI on reaction with pd and BaSO4 gives (B) of formula C2H4O. (B) on reaction with LiAIH4 gives (C) of formula C2H6O. (B) on reaction with 12 and NaOH gives (D) of formula CH2ONa and iodoform. identify A,B,CD and explain the reactions involved.
Answer:
1. From the molecular formula (A) is identified as CH3COCl (Acetyl chloride)

2. Acetyl chloride on treatment with Pd and BaSO4 gives acetaldehyde CH3CHO as (B)

3. Acetaldehyde on reaction with LiAIH4 gives ethyl alcohol as (C)

4. Acetaldehyde when treated with I2 and NaOH gives sodium formate (D) and iodoform CHI3 as products.

Question 29.
An organic compound (A) of molecular formula C7H6O gives brisk effervescence with Na2CO3. Sodium salt of (A) on treatment with sodalime gives (B) a simplest aromatic hydrocarbon. (B) on reaction with acetyichioride in the presence of anhydrous AICI3 gives (C) of formula C8H8O. (C) on treatment with conc. nitric acid and conc. sulphuric acid gives (D) of formula C8H7NO3. Identify A,BC,D,E and explain the reactions involved.
Answer:
1. (A) gives brisk effervescence with Na2CO3 solution and it must be a carboxylic acid. (A) gives brisk effervescence with NNa2CO3 solution and it must be a carboxylic acid. (A) is C6H5COOH benzoic acid.

2. Sodium salt of benzoic acid on reaction with sodalime (decarboxylation) produces benzene as (B)

3. Benzene on treatment with acetyl chloride in the presence of anhydrous AlCl3 gives acetophenone as (C)

4. Acetophenonc on reaction with conc. HNO3 and cone. H2SO4 gives m – nitro acetophenone as (D)

Question 30.
An organic compound (A) of molecular formula C2H6O on reaction with acidified K2Cr2O7 gives (B) of molecular formula C2H4O which on further oxidation gives (C) of molecular formula C2H4O2. Compound (C) reacts with (A) in the presence of conc. H2SO4 gives (D) of molecular formula C4H8O2. Identify A,B,C,D and explain the reaction Involved.
Answer:
1. An organic compound (A) of molecular formula C2H6O is identified as ethanol.

2. Ethanol on oxidation with acidified K2Cr2O7 gives first acetaldehyde as (B) which on further oxidation gives acetic acid as (C)

3. Ethanol reacts with acetic acid in the presence of conc. H2SO4, esterification take place to give ethyl acetate as product (D)

Question 31.
An organic compound (A) of molecular formula C2H4O2 gives brisk effervescence with Na2CO3. Acetyl chloride reacts with sodium acetate to give C4H6O3 as (B). (B) on reaction with PCI5 gives (C) of formula C2H10CI. (C) on reaction with ammonia gives (D) of molecular formula C2H5NO. Identify A,B,C,D and explain the reactions involved.
Answer:
1. Compound (A) gives brisk effervescence with Na2CO3 and so it must be a carboxylic acid. CH3COOH (acetic acid) is compound A.

2. Acetyl chloride on heating with sodium acetate to give acetic anhydride as (B)

3. Acetic anhydride reacts with PCI5 to give acetyl chloride CH3COCI as (C)

4. Acetyl chloride on treatment with ammonia gives acetamide as (D)

Question 32.
An organic compound (A) of molecular formula C2H4O2 reacts with PCI5 to give (B) of formula C2H3OCI. (B) on treatment with ammonia gives (C) of formula C2H5NO. (C) on reaction with Br2 and KOH gives CH5N as (D). Identify A,B,C,D and explain the reactions involved.
Answer:
1. The organic compound (A) is identified as CH3COOH (Acetic acid).

2. Acetic acid reacts with PCI5 to form acetyl chloride as (B)

3. Acetyl chloride on reaction with ammonia gives acetamide as (C)

4. Acetamide on treatment with Br2, and KOH gives methylamine as (D)

Question 33.
An organic compound (A) of molecular formula C2H5NO on treatment with LiAIH4 gives (B) of formula C2H7N. (A) on treatment with Br2 and excess of caustic alkali gives (C) of formula CH5N. (A) on treatment with phosphorous pentoxide gives (D) of molecular formula C2H3N Identify A,B,C,D and explain the reaclions involved.
Answer:
1. The organic compound (A) is identified as CH3CONH2 acetamide.

2. Acetamide on treatment with LiAlH4 gives ethylamine as product (B)

3. Acetamide on reaction with Br2 and caustic alkali gives methyl amine as (C)

4. Acetamide on treatment with P2O5 gives Aceto nitrile (or) methyl cyanide as (D)

Question 34.
An organic compound (A) of molecular formula C2H5NO on reaction with P2O5 gives C2H3N(B). (B) on hydrolysis gives (C) of formula C2H4O2 (C) on reaction with LiMB4 gives (D) formula C2H6O. Identify A,B,C,D and explain the reactions involved.
Answer:
1. (A) is identified as CH3CONH2 acetarnide.

2. Acetamide on reaction with P2O5 gives methyl cyanide as (B)

3. Methyl cyanide on acid hydrolysis gives acetic acid CH3COOH as (C)

4. Acetic acid on reaction with LiAlH4 gives ethanol as (D)

Errors

  1. Aldehydes IUPAC names
  2. Ketone – IUPAC name
  3. Ozonolysis – easy way to remember the products. Students may feel difficult in writing equation
  4. Clemmenson reduction and Wolf – Kishner reduction may get confused

Rectifications

1. The name should end with the word – al, HCHO – methanal, Aldehyde – Al, Alcohol – ol

2. The name should end with the word – one.  Propanone

3. By the either side of = bond, add one oxygen atom as products

4. The products are same, only catalyst are different

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Samacheer Kalvi 12th Commerce Company Secretary Textbook Exercise Questions and Answers

I. Choose the Correct Answer

Question 1.
Mention the status of a Company Secretaiy in a company _______
(a) A member
(b) A director
(c) An independent
(d) An employee contractor
Answer:
(d) An employee contractor

Question 2.
Who can become a secretary for a company?
(a) Individual person
(b) Partnership firm
(c) Co-operative societies
(d) Trade unions
Answer:
(a) Individual person

Question 3.
Which meeting will be held only once in the life time of the company?
(a) Statutory
(b) Annual General
(c) Extra-ordinary
(d) Class General
Answer:
(a) Statutory

Question 4.
Board Meetings to be conducted minimum _______ times in a year.
(a) 2
(b) 3
(c) 4
(d) 5
Answer:
(c) 4

Question 5.
Who is not entitled to speak at the annual general meeting of the company?
(a) Auditor
(b) Shareholder
(c) Proxy
(d) Directors
Answer:
(c) Proxy

Question 6.
Mention the company which need not convene the Statutory Meeting.
(a) Widely held public
(b) Private Limited
(c) Public Limited
(d) Guarantee having a share capital
Answer:
(b) Private Limited

Question 7.
From the date of its incorporation the First Annual General Meeting is to be conducted within _______ months.
(a) Twelve
(b) Fifteen
(c) Eighteen
(d) Twenty one
Answer:
(b) Fifteen

Question 8.
What percentage of shareholders is needed to pass special resolution?
(a) It must be unanimous
(b) Not less than 90%
(c) Not less than 75%
(d) More than 50%
Answer:
(c) Not less than 75%

Question 9.
A special resolution must be filed with the Registrar within _______
(a) 7 days
(b) 14 days
(c) 30 days
(d) 60 days
Answer:
(c) 30 days

Question 10.
A special resolution is required to _______
(a) redeem the debentures
(b) declare dividend
(c) appoint directors
(d) appoint auditor
Answer:
(d) appoint auditor

II. Very Short Answer Questions

Question 1.
Who is a Secretary?
Answer:
The person who is responsible for the general performance of an organization is called company secretary.

Question 2.
Define Meeting.
Answer:
A company meeting must be convened and held in perfect compliance with the various provisions of the Act and the rules framed thereunder.

Question 3.
What is Resolution?
Answer:
As per the Companies Act 2013, for taking any decision or executing any transaction, the consent of the shareholders, the Board of Directors and other specified is required. The decisions taken at a meeting are called resolutions

Question 4.
Write short note on ‘Proxy’.
Answer:
‘Proxy’ means a person being the representative of a shareholder at the meeting of the company. Proxy can be present at the meeting but he cannot vote.

Question 5.
What is Vote?
Answer:
The word ‘Vote’ originated from Latin word ‘Votum’ indicating one’s wishes or desire. By casting his vote one formally declares his opinion or wish in favour of or against a proposal or a candidate to be elected for an office.

III. Short Answer Questions

Question 1.
What is Special Resolution?
Answer:
A special resolution is the one which is passed by not less than 75% of majority. The number of votes, cast in favour of the resolution should be three times the number of votes cast against it.

Question 2.
What do you mean by Statutory Meeting?
Answer:
According to Companies Act, every public company, should hold a meeting of the shareholders within 6 months but not earlier than one month from the date of commencement of business of the company. This is the first general meeting of the public company, which is called the Statutory Meeting. This meeting is conducted only once in the lifetime of the company.

Question 3.
What do you understand by ‘Poll’?
Answer:
Poll means tendering or offering vote by ballot to a specially appointed officer, called the polling officer. Under the Companies Act, poll means exercising voting right in proportion to shareholder’s contribution to the paid-up capital of a limited company having a share capital.

Question 4.
Give any three cases in which an ordinary resolution need to be passed.
Answer:
An ordinary resolution is one which can be passed by a simple majority, i.e. if the members of votes cast by members, entitled to vote in favour of the resolution is more than the votes cast against the resolution.
Ordinary Resolution is required for the following matters:

  1. To change or rectify the name of the company
  2. To alter the share capital of the company
  3. To redeem the debentures

Question 5.
What resolution requires special notice?
Answer:
There are certain matters specified in the Companies Act, 2013 which may be discussed at a general meeting only if a special notice is given at least 14 days before the meeting. The intention to propose any resolution must be notified to the company. The following matters require special notice before they are discussed in the meeting:-

  1. To appoint an auditor, a person other than a retiring auditor
  2. To provide expressly that a retiring Auditor shall not be reappointed
  3. To remove a director before the expiry of his period of office
  4. To appoint a director in the place of a director so removed

IV. Long Answer Questions

Question 1.
Elaborate the functions of the Company Secretary.
Answer:
The functions of the Company Secretary may be divided into two types. They are:

  1. Statutory functions
  2. Non-Statutory functions

Statutory Functions: As the principal officer of the company, the secretary must observe all the legal formalities in respect of the provisions of the Companies Act and other laws, for the activities of the company.
According to Companies Act 2013:

  1. To sign document and proceedings requiring authentication by the company
  2. To maintain share registers and register of directors and of contracts.
  3. TO give notice to register for increase in the share capital
  4. To send notice of general meeting to every member of the company
  5. To prepare minutes of every general meeting and board meeting within 30 days

Non-Statutory Functions: The secretary has to discharge non-statutory functions in relation to directors, shareholders and office and staff.
Functions in Relation to Directors: A company secretary acts under the full control of the board of directors and carry out the instructions of the directors.

The secretary will arrange board meetings issuing notice, and preparing agenda of meetings, recording the attendance and minutes of meetings.

Functions in Relation to Shareholders: The company secretary must serve in the best interests of the shareholders.
He has to arrange the issue of allotment letters, call letters, letters of regret, share certificates, and share warrants to Shareholders.

Functions in Relation to Office and Staff: The secretary is responsible for smooth functioning of the office work. He exercises an overall supervision, control and co-ordination of all clerical activities in the office.

Question 2.
Discuss the liabilities of Company Secretary.
Answer:
As an officer, a company secretary has extensive duties and liabilities. The success of the company depends upon his efficient functions and capacity to perform.
Liabilities:

  1. It is duty of the secretary to arrange for Board meetings and shareholders annual general meeting.
  2. The secretary controls and supervises the day-to-day activities of the company.
  3. Also he should prepare details for issue of allotment letters, share certificates and dividend warrants.
  4. To arrange for filing statement in lieu of prospectus.
  5. The secretary should send notice of general meeting to every member of the company.
  6. Being a principal officer, a company secretary can sign contracts and proceedings of company meetings.
  7. (He is liable to maintain share registers and register of directors and contracts.
  8. To prepare minutes of every general meeting and Board meetings within 30 days.

Question 3.
Briefly state different types of company meetings.
Answer:
A Company can convene meetings to discuss the performance of the company and also to take decisions. Under the companies Act 2013, company meetings may be classified as below:
(i) Meetings of Shareholders: The meeting held for the shareholders of the company is shareholders meeting. This may be divided as follows: .
(a) Statutory Meeting: Every public company should hold a meeting of the shareholders within 6 months but not earlier than one month from the commencement of the business.
(b) Annual General Meeting: Every year a meeting is held to transact the ordinary business of the company. It is called annual general meeting.
(c) Extra-Ordinary General Meeting: If any meeting conducted in between two annual general meetings to deal with some urgent or special or extraordinary nature of business is called as extra-ordinary general meeting.

(ii) Meeting of the Board of Directors: To decide policy matters of the company, the board of directors meet frequently, which is known as meeting of the board of directors.
(a) Board Meetings: Meetings of the directors are called board meetings. It may be convened to discuss the business and take formal decisions.
(b) Committee Meetings: Every listed company and every other public company having a capital of ?10 crore is required to have audit committee. The meeting held by this committee is known as committee meetings.

(iii) Special Meeting:
(a) Class Meeting: Meetings held by a particular class of share or debenture holders is
known as Special or Class meeting, e.g. preference shareholders or debenture holders meeting. .
(b) Meetings of the Creditors: These are not meetings of a company. Meetings held with the creditors to discuss any crisis about the financial matters.

Question 4.
Describe the different types of resolutions which company may pass with suitable matters required for each type of resolution.
Answer:
A motion, with or without the amendments which is put to vote at a meeting and passed with the required quorum becomes resolution. Resolution may be classified into three types. They are: Ordinary resolution, Special resolution and resolution requiring special notice.
(i) Ordinary Resolution: An ordinary resolution is one which can be passed by a simple majority.
Ordinary Resolution is required for the following matters:
(a) To change or rectify the name of the company
(b) To alter the share capital of the company
(c) To redeem the debentures
(d) To declare the dividends
(e) To appoint the directors

(ii) Special Resolution: A special resolution is the one which is passed by not less than 75% of majority.
Special Resolution is required for the following matters:
(a) To change the registered office of the company
(b) To alter the Articles of Association
(c) To commence any new business
(d) To appoint the auditor for the company

(iii) Resolution requiring Special Notice: There are certain matters specified in the Companies Act, 2013 which may be discussed at a general meeting only if a special notice is given at least 14 days before the meeting.
The following matters require special notice:
(a) To remove a director before the expiry of his period
(b) To appoint a director in the place of a director so removed

Question 5.
Explain different types of open and secret types of voting.
Answer:
The word ‘Vote’ originated from Latin word ‘Votum’ indicating one’s wishes or desire. He can vote formally by expressing his opinion or wish in favour or against a proposal.
Types of Voting: There are two methods of voting viz, open and secret procedures.
(i) Open Voting: This type of voting has no secrecy as all the members assembled can see – voting. There are two types of open voting namely voice voting and voting by show of hands.
(a) By Voice: Voice voting is a popular type of voting in which the chairman allows the members to raise their voice in favour or against an issue ‘Yes’ for approval and ‘No’ for rejection.
(b) By Show of Hands: Under this method, the chairman requests the members to raise their hands for the proposal.

(ii) Secret Procedure: Secret procedure is adopted to decide certain vital issues. It may be of two types:
(a) By Ballot: Under this system, ballot paper bearing serial number is given to the members to record their opinion by marking with the symbol.
(b) Postal Ballot: Big companies or big associations having members scattered all over . the country follow this method of voting. Under this method, the members or voters fill
in the ballot papers sent by the company and return them in sealed covers.

Samacheer Kalvi 12th Commerce Company Secretary Additional Questions and Answers

I. Choose the Correct Answer

Question 1.
A statutory meeting can be held within _________ months.
(a) 10
(b) 5
(c) 6
(d) 3
Answer:
(c) 6

Question 2.
The word ‘Vote’ originated from the Latin word _________ indicating one’s wishes or desires.
(a) Votum
(b) _______
(c) _______
(d) _______
Answer:
(a) Votum

Question 3.
An ordinary resolution is one which can be passed by a _________ majority.
(a) simple
(b) special
(c) high
(d) low
Answer:
(a) simple

II. Very Short Answer Questions

Question 1.
Name the various kinds of meetings of shareholders.
Answer:
The meetings of the shareholders can be divided into three kinds: They are

  1. Statutory meeting
  2. Annual general meeting
  3. Extra-ordinary general meeting

Question 2.
Write a note on class meeting.
Answer:
Meetings, which are held by a particular class of share or debenture holders is known as class meeting, e.g. preference shareholders meetings or debenture holders meeting.

III. Short Answer Questions

Question 1.
How the company secretary is appointed?
Answer:
As per section 2 (247, 203, 204) of companies Act 2013, the provisions are given for appointment of company secretary. Only an individual who is a member of Institute of Company Secretaries of India can be „ appointed as a company secretary. There are two methods of appointment of company secretary. They are given below:

  1. By the Promoters: The first secretary of a company is appointed by the promoters at pre-incorporation stage.
  2. By the First board of Directors: After the company has been registered, the first board of directors appoints the secretary at the first board meeting.

Case study

Case 1:
Mr R, as the secretary of the Muraliviki Co., signed a letter to its bank, forwarding a ‘resolution’ of the board of directors. The resolution named three directors and instructed the bank to pay cheques signed by any two of them and countersigned by the secretary. Specimen signatures were attached. The instruction was entirely in accordance with the company’s memorandum and articles. However, there had never been any proper appointment of directors or a secretary by the company. Those who had formed the company had assumed their roles. Following the letter, the bank had honoured cheques in accordance with the instructions contained in the letter. The question was, whether, the company was bound by the cheques. Comment.
Answer:
Yes, the company was bound liable for the cheques given.
Because, the company has instructed the bank to pay cheques signed by any two of the director and countersigned by the Secretary. So the bank honoured the cheques issued by the company.

Case 2:
A contract between Muthumani Ltd and Mr. V, one of its director is referred to a general meeting for its approval. At the meeting, Mr. V voted for the resolution and all others against it. But as V held majority of shares and was entitled to majority of votes, the resolution was passed. Is the contract binding on the company?
Answer:
No. The contract is not binding the company. Because the director Mr.V is having majority of shares. So the resolution is passed by Mr.V, by having majority of votes.

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