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You can Download Samacheer Kalvi 6th Science Book Solutions Guide Pdf, Tamilnadu State Board help you to revise the complete Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 6th Science Solutions Term 1 Chapter 6 Health and Hygiene

Samacheer Kalvi 6th Science Health and Hygiene Textual Evaluation

I. Choose the appropriate answer

Samacheer Kalvi Guru 6th Science Question 1.
Our body needs _______ for muscle-building.
(a) Carbohydrate
(b) Fat
(c) Protein
(d) Water
Answer:
(c) Protein

Health And Hygiene Class 6 Questions And Answers Samacheer Question 2.
Scurvy is caused due to the deficiency of ………..
(a) Vitamin A
(b) Vitamin B
(c) Vitamin C
(d) Vitamin D
Answer:
(c) Vitamin C

Samacheer Kalvi 6th Science Question 3.
Calcium is an example of a _______
(a) Carbohydrate
(b) Fat
(c) Protein
(d) Minerals
Answer:
(d) Minerals

Samacheer Kalvi 6th Science Guide Question 4.
We should include fruits and vegetables in our diet, because ……….
(a) They are the best source of Carbohydrates.
(b) They are the best source of Proteins.
(c) They are rich in minerals and vitamins.
(d) They have high water content.
Answer:
(c) They are rich in minerals and vitamins.

Samacheer Kalvi 6th Science Book Back Answers Question 5.
Bacteria are very small _______ microorganism.
(a) Prokaryotic
(b) Eukaryotic
(c) Protozoa
(d) Acellular
Answer:
(a) Prokaryotic

II. True or false

6th Science Samacheer Kalvi Question 1.
There are three main nutrients present in food.
Answer:
False. There are six main nutrients present in food.

Samacheer Kalvi.Guru 6th Science Question 2.
Fats are used as an energy store by our body.
Answer:
True.

Samacheer Kalvi Science 6th Standard Question 3.
All bacteria have flagella.
Answer:
False. Not all bacteria have flagella only, some bacteria have flagella.

Samacheer Kalvi 6 Science Question 4.
Iron helps in the formation of haemoglobin.
Answer:
True

Samacheer Kalvi 6th Science Solution Question 5.
Virus can grow and multiply outside host.
Answer:
False. Virus can grow and multiply inside host.

III. Fill in the Blanks.

1. Malnutrition leads to _______
2. Iodine deficiency leads to _______ in adults.
3. Vitamin D deficiency causes _______.
4. Typhoid is transmitted due to contamination of _______ and water.
5. Influenza is a _______ disease.

Answers:

1. deficiency disease
2. goitre
3. Rickets
4. food
5. viral (virus)

IV. Complete the Analogy.

Samacheer Kalvi 6th Standard Question 1.
Rice: Carbohydrate :: Pulses: _______
Answer:
Protein.

Samacheer Kalvi 6th Science Solutions Question 2.
Vitamin D : Rickets :: Vitamin C: _______
Answer:
Scurvy.

Samacheer Kalvi 6th Science Book Question 3.
Iodine: Goitre :: Iron: _______
Answer:
Anaemia.

Samacheer Kalvi Class 6 Science Solutions Question 4.
Cholera: Bacteria :: Smallpox: _______
Answer:
Virus.

V. Match the following

1. Vitamin A – Rickets
2. Vitamin B – Night blindness
3. Vitamin C – Sterility
4. Vitamin D – Beriberi
5. Vitamin E – Scurvy

Answer:

1. Vitamin A – Night blindness
2. Vitamin B – Beri beri
3. Vitamin C – Scurvy
4. Vitamin D – Rickets
5. Vitamin E – Sterility

VI. Complete the diagram

Question:

Answer:

VII. Write a Short Answer.

Samacheer Kalvi Science 6th Question 1.
Write two examples for each of the following.
Answer:
(a) Food items were rich in fat – Egg yolk, meat.
(b) Vitamin deficiency – diseases.
(c) Vitamin C – Scurvy
(d) Vitamin D – Rickets.

6th Samacheer Kalvi Science Question 2.
Differentiate between carbohydrate and protein.
Answer:
Carbohydrate:

1. Energy giving component of the food.
2. The sources of carbohydrate are nuts, fruits, rice and maize.

Protein:

1. It is body building foods.
2. The sources of proteins are pulses, soyabean, nuts, egg, and fish.

6th Standard Science Question 3.
Define the term ‘balanced diet’?
Answer:
A balanced diet is a diet which contains an adequate amount of all the necessary nutrients like carbohydrate fat protein minerals and vitamins required for healthy growth and activity.

Samacheer Kalvi Guru 6th Question 4.
Why should the fruits and vegetables not to be washed after cutting?
Answer:
We should not wash the fruits and vegetables after cutting, because the minerals and protein in the fruits and vegetables will also be washed away.

Samacheer Kalvi 6th Solutions Question 5.
Write any two viral diseases.
Answer:

1. AIDS
2. Hepatitis.

Samacheerkalvi.Guru 6th Science Question 6.
What is the main feature of a microorganism?
Answer:
Microorganism will be seen with the help of microscope. They are very small in size.

VIII. Long Answer.

Samacheer Kalvi Guru 6th Standard Science Question 1.
Tabulate the vitamins and their corresponding deficiency diseases.
Answer:

Samacheer Kalvi 6th Science Health and Hygiene Intext Activities

Samacheer Kalvi Guru 6th Science Guide Activity 1

Identify the following food items and complete the table given below.

Answer:

Samacheer Kalvi Guru 6 Science Question 1.
Do your favorite foods make you healthy?
Answer:
Some of my favorite foods make me healthy.

Samacheer Kalvi 6th Question 2.
Do you choose your food by taste or by its nutritive value?
Answer:
I choose my food by taste and also by its nutritive value.

Samacheer Kalvi 6th Guide Activity 2
Collect as many food items as you can and classify them according to the major nutrient content in it.
Answer:

Activity 3
Aim: To test the presence of Carbohydrate as Starch in the given food item.

Question 1.
What do you need?
Answer:
Boiled potato, dropper and dilute Iodine solution.

Question 2.
How to do?
Answer:
Smash the boiled potato. Add two or three drops of dilute Iodine solution on the Sample.

Question 3.
What do you observe?
Answer:
The potato turns blue-black in colour.

Question 4.
What do you infer?
Answer:
Iodine reacts with Starch to form Starch-Iodine complex which is blueblack in colour. Thus, the appearance of blue-black colour confirms the presence of Starch in the food item.

Activity 4
Aim: To test the presence of Fat in the given food item.

Question 1.
What do you need?
Answer:
Coconut Oil, groundnut oil, and any Paper.

Question 2.
How to do?
Answer:
Pour few drops of oil onto the paper and rub it gently with your finger. In case of ground nut, crush the groundnut and place it on a paper. Now rub the groundnut on the paper.

Question 3.
What do you see?
Answer:
The paper turns translucent and becomes greasy.

Question 4.
What do you learn?
Answer:
The given food sample contains fat.

Activity 5
Aim: To test the presence of Protein in the given food item.

Question 1.
What do you need?
Answer:
Egg white, Copper sulphate solution, Sodium hydroxide, Test tube and Bunsen burner.

Question 2.
How to do?
Answer:
Take a small amount of the food sample (egg white) and put in the test tube. Add some water to the test tube and shake it. Next, heat the test tube for about one minute. After the test tube has cooled down, add two drops each of Copper sulphate solution and Sodium hydroxide to it.

Question 3.
What do you see?
Answer:
The food sample turns purple or violet.

Question 4.
What do you learn?
Answer:
Change in colour of the given food sample turns purple or violet confirms the presence of Protein.

Just Think

A medical camp was conducted in School. Most of the children were healthy. Some of the students had some health issues
Priya had bleeding gums.
Raja could not see clearly in dim light.
Arun had bent legs .
Can you guess what could be the reasons?

• Priya was affected by Vitamin ‘C’ deficiency. So she had bleeding gums.
• Raja was affected by vitamin ‘A’ deficiency. So he could not see clearly in dim light.
• Arun was affected by vitamin ‘D’ deficiency. So he had bent legs.

Activity 6

Question 1.
Make your food little healthier. What do you need?
Answer:
A small cup of green gram seeds, Water and thin cloth.

Question 2.
How to do?
Answer:
Soak the green gram seeds in water over night. Take out the seeds and strain the water. Wrap the seeds in wet thin cloth. Keep it for a day or two. Sprinkle some water whenever it is dry.

Question 3.
What do you see?
Answer:
You can see white sprouts coming out of the seeds.

Question 4.
What do you learn?
Answer:
Green gram sprouts are low in calories, have fibre and Vitamin B. It has comparatively high amount of vitamin C and vitamin K.

Complete the following Table – 4

Answer:

Activity 7

Question:
Why do we need a balanced diet?
Prepare a diet chart to provide balanced diet to a 12 year old child. The diet chart should include food item which are not expensive and are commonly available in your area.
Answer:
We need a balanced diet because,
a balanced diet contains sufficient amount of various nutrients to ensure good health.
Balance diet for 12 year old boy / girl.

Activity 8

Question:
Visit a nearby Anganwadi centre and find the steps taken by the government to overcome malnutrition and ensure health in the age group 0-5 years.
Answer:
Activity to be done by the students themselves

Activity 9

One day Rahim, a class six boy vomited three times. He was looking tired and dehydrated. His mother who was a nurse prepared a solution and gave it to him drink. He felt better after sometime and asked his mother what the solution was. His mother said it was Oral Rehydration Solution – ORS. Shall we see what an ORS is? Vomiting or loose motions result in loss of water and cause salt imbalance in the body. Loss of water (dehydration) can lead to serious problems. This can be prevented by consuming ORS at short intervals.

Follow the steps to make ORS at home:

• Take a litre of boiled water. Cool it.
• Add half a teaspoon of salt and six teaspoons of sugar to it.
• You can also add a few drops of lemon juice to it. Stir it and give it to the person suffering from vomiting, loose motions or dehydration.

Answer:
Activity to be done by the students themselves

Discuss in your class room
“Is virus a living thing or non living thing?”
Answer:
Viruse is a non-living thing.

Reasons:

1. Virus is an a cellular, meaning it lacks a cell membrane.
2. It is an obligate parasite. It requires a host cell to reproduce.
3. It lacks an energy-generating system. It cannot produce its own energy.
4. It cannot perform metabolic activities.
5. Viruses are not composed of cells and do not reproduce themselves from other pre-existing viruses.
6. The genetic material (DNA or RNA) inside the virus invades the living host cell, and causes the cell to replicate virus parts and assemble them to make new viruses, which are released to infect more cells.

Samacheer Kalvi 6th Science Health and Hygiene Additional Questions

I. Choose the correct answer

Question 1.
_______ provides more energy than Carbohydrates.
(a) Fat
(b) Vitamin
(c) Protein
(d) Water
Answer:
(a) Fat

Question 2.
Name the vitamin which is rich in Gooseberry.
(a) C
(b) E
(c) B
(d) D
Answer:
(c) B

Question 3.
Among the Vitamins, which one is the water soluble Vitamin?
(a) Vitamin A
(b) Vitamin B
(e) Vitamin D
(d) Vitamin E
Answer:
(b) Vitamin B

Question 4.
Name the vitamin present in Muringa leaves
(a) A and B
(b) C and D
(c) K and A
(d) A and C
Answer:
(d) A and C

Question 5.
_______ is made in our skin using sunlight.
(a) Vitamin D
(b) Vitamin C
(c) Vitamin A
(d) Vitamin B
Answer:
(a) Vitamin D

Question 6.
_______ are required for growth as well as for the regulation of normal body function.
(a) Fats
(b) Proteins
(c) Carbohydrates
(d) Minerals
Answer:
(d) Minerals

Question 7.
80% of the world production of Moringa leaves is in _______
(a) China
(b) Germany
(c) India
(d) Canada
Answer:
(c) India

Question 8.
Any human being should take minimum _______ of water every day.
(a) 2 litres
(b) 3 litres
(c) 8 litres
(d) 6 litres
Answer:
(a) 2 litres

Question 9.
_______ is the bacterial disease and it transmits through contamination of wounds, with the bacteria.
(a) Cholera
(b) Tetanus
(c) Typhoid
(d) Pneumonia
Answer:
(b) Tetanus

Question 10.
_______ is a cellular agent that replicates only inside the cells of the other living organism.
(a) Bacteria
(b) Protozoa
(c) Fungi
(d) Virus
Answer:
(d) Virus

Il. Fill in the blanks.

Question 1.
We can obtain Carbohydrates in the form of _______
Answer:
Sugar, Starch, Dietary Fibers

Question 2.
Vitamins are called as _______ food.
Answer:
Protective

Question 3.
The vitamins A, D, E, K are _______ soluble vitamins.
Answer:
Fat

Question 4.
_______ is a disease, due to the deficiency of Vitamin E.
Answer:
Nervous Weakness

Question 5.
Moringa leaves contains powerful anti _______
Answer:
Oxidantsl

Question 6.
Skinny appearance and slow body growth are the symptoms of _______ disease.
Answer:
Marasmusl

Question 7.
_______ is strengthening muscles and the cardiovascular system.
Answer:
Physical exercisel

Question 8.
_______ can kill damage or change the cells and make you sick.
Answer:
Virus

Question 9.
Sun screen lotion reduces your skin’s ability to produce _______ by up to 95%.
Answer:
Vitamin D

Question 10.
Goose bernes contain nearly _______ the vitamin C than orange.
Answer:
20 times

Question 11.
India has the _______ highest number of obese children ¡n the world.
Answer:
Second

III. True of false. If false give the correct answer.

Question 1.
Minerals are required for carrying out various biochemical reactions in our body.
Answer:
False. Vitamins are required for carrying out various biochemical reactions in our body.

Question 2.
Night blindness is a disease due to deficiency of Vitamin A.
Answer:
True.

Question 3.
Vitamin D abundantly found in orange and gooseberry.
Answer:
False. Vitamin C abundantly found in orange and gooseberry.

Question 4.
Sun screen lotion reduces ability to produce Vitamin D. It leads to Vitamin D deficiency diseases.
Answer:
True.

Question 5.
Iodine maintains strong bones, teeth and helps in clotting of blood.
Answer:
False. Calcium maintains strong bones, teeth and helps in clotting of blood.

Question 6.
Moringa leaves are rich in the minerals potassium, calcium and iron.
Answer:
True.

IV. Complete the Analogy

Question 1.
Polio : Virus :: Tetanus : _______
Answer:
Bacteria

Question 2.
_______ : Diarrhoea:: Marasmus: Slow body growth.
Answer:
Kwashiorkar

Question 3.
Synthesis of thyroid harmone: Iodine:: Formation of haeniogiobin: _______
Answer:
Iron

Question 4.
Fish oil : Vitamin D :: Vegetable oil : _______
Answer:
Vitamin II

Question 5.
Vitamin K : Clotting of blood :: Vitamin E : _______
Answer:
Fertility

Question 6.
Protein: Soya bean:: Fat: _______
Answer:
Meat

V. Match the following.

Question 1.

1. Carbohydrate – (a) Carrying out various biochemical reactions
2. Proteins – (b) Regulation of normal body function
3. Vitamins – (c) energy giving component
4. Minerals – (d) Body building food

Answer:

1. – c
2. – d
3. – a
4. – b

Question 2.

Answer:

1. – d
2. – e
3. – b
4. – a
5. – c

VI. Complete the diagram

Answer:
A – Exercise
B – Yoga.

VII. Short Answers.

Question 1.
Define homeostasis.
Answer:
It is to maintain a stable equilibrium of body in accordance with the pressures and changes of body environment.

Question 2.
What are the nutrients obtained from food?
Answer:

1. Carbohydrate
2. Proteins
3. Fats
4. Vitamins
5. Minerals
6. Water.

Question 3.
What is meant by deficiency diseases?
Answer:
The diseases that are caused due to lack of nutrients in the diet are called deficiency diseases.

Question 4.
Sun Screen lotion is not good for our health. Justify.
Answer:
Sun Screen lotion reduces our skin’s ability to produce vitamin D upto 95%. It may lead to Vitamin D deficiency. So it not for good our health.

Question 5.
Fill in the blanks.
A – Calcium – Rickets
Phosphorus – …………
Answer:
Osteomalacia

B – Iodine – cretinism
Iron – ………….
Answer:
anaemia

Question 6.
What are the nutrients present in Moringa leaves?
Answer:
Moringa leaves are rich in Vitamin A, Vitamin C, Potassium, Calcium, Iron and Protein. It also contains powerful anti-oxidants.

Question 7.
How does Balanced diet help in our body?
Answer:
Balanced diet helps in our body, in the following ways :

1. An increased capacity to work
2. Good physical and mental health
3. Increased capacity to resist diseases.
4. Help in proper growth of the body.

Question 8.
Give some mineral deficiency diseases.
Answer:
Rickets, Osteomalatia, Cretinism in Child, Goitre in adult, Anaemia are the mineral deficiency diseases.

Question 9.
How does Physical exercise help us?
Answer:
Physical exercise helps us in the following ways:

1. increase in growth and development
2. strengthening muscles and the cardiovascular system
3. developing athletic skills
4. weight loss or maintenance, and enjoyment.

Question 10.
How are the following bacterial diseases transmitted?
(i) Cholera
(ii) Tetanus
(iii) Typhoid
(iv) Tuberculosis
Answer:

Question 11.
Name the countries which import Moringa leaves.
Answer:
China, United States, German, Canada, South Korea and European Countries import Moringa leaves.

Question 12.
Define health.
Answer:
Health is a state of complete physical, mental and social well-being and not merely absence of diseases. Eating a healthy diet keeps us physically and mentally fit.

Question 13.
Name the four major groups of Microbes.
Answer:
Microbes divided into four major groups. They are

• Bacteria
• Virus
• Protozoa
• Fungi

Question 14.
Define Disease.
Answer:
Disease is a definite pathological process having a characteristic set of signs and symptoms.

Question 15.
What is a Retrovirus?
Answer:
A Virus that contains R.N.A. instead of D.N.A. is called a Retrovirus.

VIII. Long Answer.

Question 1.
Fill in the Table :

Answer:

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Tamilnadu Samacheer Kalvi 12th Chemistry Solutions Chapter 6 Solid State

All concepts are explained in an easy way on our website. So, students can easily learn and practice Tamilnadu State Board 12th Chemistry Chapter 6 Solid State Question and Answers. You can enjoy the digitized learning with the help of the Tamilnadu State Board Chemistry Online Material.

Samacheer Kalvi 12th Chemistry Solid State Text Book Evalution

I. Choose the correct answer.

12th Chemistry Chapter 6 Book Back Answers Question 1.
Graphite and diamond are ………..
(a) Covalent and molecular crystals
(b) ionic and covalent
(c) both covalent crystals
(d) both molecular crystals
Answer:
(c) both covalent crystals

12th Chemistry Solid State Book Back Answers Question 2.
An ionic compound A_x B_y crystallizes in fee type crystal structure with B ions at the centre of each face and A ion occupying centre of the cube, the correct formula of A B is ………..
(a) AB
(b) AB₃
(c) A₃B
(d) A₈B₆
Answer:
(b) AB₃
Hint: Number of A ions = \(\left( \frac { { N }_{ c } }{ 8 } \right)\) = \(\left( \frac { 8 }{ 8 } \right)\) = 1
Number of B ions = \(\left( \frac { { N }_{ f } }{ 2 } \right)\) = \(\left( \frac { 6 }{ 2 } \right)\) = 3
Simplest formula AB₃

12th Chemistry Unit 6 Book Back Answers Question 3.
The rano of close packed atoms to tetrahedral hole in cubic packing is ………..
(a) 1:1
(b) 1:2
(c) 2:1
(d) 1:4
Answer:
(b) 1:2
Hint: If number of close packed atoms =N; then, The number of Tetrahedral holes formed = 2N, Number of Octahedral holes formed = N. Therefore N : 2N = 1 : 2

Solid State Questions Pdf Question 4.
Solid CO₂ is an example of ………..
(a) Covalent solid
(b) metallic solid
(c) molecular solid
(d) ionic solid
Answer:
(c) molecular solid
Hint: Lattice points are occupied by CO₂ molecules

Solid State Numericals Class 12 Question 5.
Assertion: monoclinic sulphur is an example of monoclinic crystal system.
Reason: for a monoclinic system, a \(\neq\) b \(\neq\) c and α = γ = 90° , β \(\neq\) 90°.
(a) Both assertion and reason are true and reason is the correct explanation of assertion.
(b) 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) Both assertion and reason are true and reason is the correct explanation of assertion

Chemistry Class 12 Samacheer Kalvi Question 6.
In calcium fluoride, having the flurite structure the coordination number of Ca²⁺ ion and F Ion are ………..
(a) 4 and 2
(b) 6 and 6
(c) 8 and 4
(d) 4 and 8
Answer:
(c) 8 and 4
Hint: CaF₂ has cubical close packed arrangement Ca²⁺ ions are in face centered cubic arrangement, each Ca²⁺ ions is surrounded by 8 F^– ions and each F^– ion is surrounded by 4 Ca²⁺ ions.Therefore coordination number of Ca²⁺ is 8 and of F^– is 4 pattern is (NA is the Avogadro number)

Samacheer Kalvi 12th Chemistry Question 7.
The number of unit cells in 8gm of an element X (atomic mass 40) which crystallizes in bcc pattern is (N_A is the Avogadro number)
(a) 6.023 x 10²³
(b) 6.023 x 10²²
(c) 60.23 x 10²³
(d) \(\left( \frac { 6.023\times { 10 }^{ 23 } }{ 8\times 40 } \right)\)
Answer:
(b) 6.023 x 10²²
Hint: In bcc unit cell, 2 atoms = 1 unit cell
Number of atoms in 8g of element is, Number of moles = \(\left( \frac { 8g }{ 40g,{ mol }^{ -1 } } \right)\) = 0.2 mol
1 mole contains 6.023 x 10²³ atoms 0.2 mole contains 0.2 x 6.023 x 10²³ atoms
\((\frac{1unit cell}{2 atoms})\) x 0.2 x 6.023 x 10²³ = 6.023 x 10²² unit cells

Samacheer Kalvi Guru 12th Chemistry Question 8.
The number of carbon atoms per unit cell of diamond is ………..
(a) 8
(b) 6
(c) 1
(d) 4
Answer:
(a) 8
Hint: In diamond carbon forming fee. Carbon occupies comers and face centres and also occupying half of the tetrahedral voids.
\(\left( \frac { { N }_{ c } }{ 8 } \right)\) + \(\left( \frac { { N }_{ f } }{ 2 } \right)\) + 4C atoms in Td voids
\(\left( \frac { 8 }{ 8 } \right)\) + \(\left( \frac { 6 }{ 2 } \right)\) + 4 = 8.

Samacheerkalvi.Guru 12th Chemistry Question 9.
In a solid atom M occupies ccp lattice and \(\left( \frac { 1 }{ 3 } \right)\) of tetrahedral voids are occupied by atom N. Find the formula of solid formed by M and N.
(a) MN
(b) M₃N
(C) MN₃
(d) M₃N₂
Answer:
(d) M₃N₂
Hint: If the total number of M atoms is n, then the number of tetrahedral voids = 2 n. Given that \(\left( \frac { 1 }{ 3 } \right)\)^rd of tetrahedral voids are occupied i.e., \(\left( \frac { 1 }{ 3 } \right)\) x 2 n are occupied by N atoms.
∴ M : N ⇒ n : \(\left( \frac { 2 }{ 3 } \right)\)
1 : \(\left( \frac { 1 }{ 3 } \right)\) 3 : 2 ⇒ M₃N₂

12th Chemistry Samacheer Kalvi Question 10.
The Composition of a sample of wurizite is Fe_0.93 O_1.00 what % of Iron present in the form of Fe³⁺
(a) 16.05%
(b) 15.05%
(c) 18.05%
(d) 17.05%
Answer:
(b) 15.05%
Hint: Let the number of Fe²⁺ ions in the crystal be x. The number of Fe³⁺ ions in the crystal be y. Total number of Fe²⁺ and Fe³⁺ ions is x + y. Given that x + y = 0.93. The total charge= 0 x (2+) + (0.93 – x) (+ 3) – 2 = 0 ⇒ 2x + 2.97 – 3x – 2 = 0 x 0.79 Percentage of Fe³⁺ = \(\left( \frac { (0.93-0.79) }{ 0.93 } \right)\)100 = 15.05%

Samacheer Kalvi Guru Class 12 Chemistry Question 11.
The ionic radii of A⁺ and B^– are 0.98 x 10^-10 m and 1.81 x 10^-10 m , the coordination number of each ion in AB is ………..
(a) 8
(b) 2
(c) 6
(d) 4
Answer:
(c) 6
Hint: \(\frac { { r }_{ { c }^{ 1 } } }{ { r }_{ { A }^{ – } } }\) = \(\left( \frac { 0.98\times { 10 }^{ -10 } }{ 1.81\times { 10 }^{ -10 } } \right)\) = 0.54. It is in the range of 0.414, 0.732,hence the coordination number of each ion is 6.

Class 12 Chemistry Samacheer Kalvi Question 12.
CsCl has bcc arrangement, its unit cell edge length is 400pm, its inter atomic distance is ………..
(a) 400pm
(b) 800pm
(c) \(g\sqrt { 3 } \) x 100pm
(d) \(\left( \frac { \sqrt { 3 } }{ 2 } \right)\) x 400 pm
Answer:
(d) \(\left( \frac { \sqrt { 3 } }{ 2 } \right)\) x 400 pm
Hint:
\(g\sqrt { 3 } \)a = r_Cs⁺ + 2r_Cs^– + r_Cs⁺
\(\left( \frac { \sqrt { 3 } }{ 2 } \right)\)a = (r_Cs⁺ + r_Cs^–)
\(\left( \frac { \sqrt { 3 } }{ 2 } \right)\)400 = inter ionic distance

12 Chemistry Samacheer Kalvi Question 13.
A solid compound XY has NaCl structure, if the radius of the cation is 100pm , the radius of the anion will be ………..
(a) \(\left( \frac { 100 }{ 0.414 } \right)\)
(b) \(\left( \frac { 0.732 }{ 100 } \right)\)
(c) 100 x 0.414
(d) \(\left( \frac { 0.414 }{ 100 } \right)\)
Answer:
(a) \(\left( \frac { 100 }{ 0.414 } \right)\)
Hint: For an fcc structure

12th Chemistry Solutions Samacheer Kalvi Question 14.
The vacant space in bcc lattice unit cell is ………..
(a) 48%
(b) 23%
(c) 32%
(d) 26%
Answer:
(c) 32%
Hint: Packing efficiency = 68%. Therefore empty space percentage = (100-68) = 32%

Solid State Book Back Answers Question 15.
The radius of an atom is 300pm, if it crystallizes in a face centered cubic lattice, the length of the edge of the unit cell is ………..
(a) 488.5pm
(b) 848.5pm
(c) 884.5pm
(d) 484.5pm
Answer:
(b) 848.5pm
Hint: Let edge length = a \(g\sqrt { 2 } \)a = 4r
a = \(\left( \frac { 4\times 300 }{ \sqrt { 2 } } \right)\)
a = 600 x 1.414
a = 848.4 pm

Samacheer Kalvi Guru Chemistry Question 16.
The fraction of total volume occupied by the atoms in a simple cubic is ………..
(a) \(\left( \frac { \pi }{ 4\sqrt { 2 } } \right)\)
(b) \(\left( \frac { \pi }{ 6 } \right)\)
(c) \(\left( \frac { \pi }{ 4 } \right)\)
(d) \(\left( \frac { \pi }{ 3\sqrt { 2 } } \right)\)
Answer:
(b) \(\left( \frac { \pi }{ 6 } \right)\)
Hint:

12th Chemistry Solid State Pdf Question 17.
The yellow colour in NaCl crystal is due to ………..
(a) excitation of electrons in F centers
(b) reflection of light from Cl^– ion on the surface
(c) refraction of light from Na⁺ ion
(d) all of the above
Answer:
(a) excitation of electrons in F centers

Solid State Chemistry Class 12 Pdf Question 18.
If ’a’ stands for the edge length of the cubic system; sc ,bcc, and fcc. Then the ratio of radii of spheres in these systems wilL be respectively.

Answer:

Hing:

Solid State Chemistry Class 12 Question 19.
If a is the length of the side of the cube, the distance between the body centered atom and one comer atom in the cube will be ………..
(a) \(\left( \frac { 2 }{ \sqrt { 3 } } \right) a\)
(b) \(\left( \frac { 4 }{ \sqrt { 3 } } \right) a\)
(c) \(\left( \frac { \sqrt { 3 } }{ 4 } \right) a\)
(d) \(\left( \frac { \sqrt { 3 } }{ 2 } \right) a\)
Answer:
(d) \(\left( \frac { \sqrt { 3 } }{ 2 } \right) a\)
Hint: If a is the length of the side, then the length of the leading diagonal passing through the body centered atom is \(g\sqrt { 3 } \)a. Required distance = \(\left( \frac { \sqrt { 3 } }{ 2 } \right) a\)

Question 20.
Potassium has a bcc structure with nearest neighbor distance 4.52 A. its atomic weight is 39. Its density will be ………..
(a) 915 kg m^-3
(b) 2142 kg m^-3
(c) 452 kg m^-3
(d) 390 kg m^-3
Answer:
(a) 915 kg m^-3
Hint:
(ρ) = \(\frac { nM }{ { a }^{ 3 }{ N }_{ A } }\)For bcc n = 2 M 39. Nearest distance 2r = 4.52

ρ = 915 kg m^-3 N_A

Question 21.
Schottky defect in a crystal is observed when ………..
(a) unequal number of anions and anions are missing from the lattice
(b) equal number of anions and anions are missing from the lattice
(e) an ion leaves its normal site and occupies an interstitial site
(d) no ion is missing from its lattice.
Answer:
(b) equal number of anions and anions are missing from the lattice

Question 22.
The cation leaves its normal position in the crystal and moves to some interstitial position, the defect in the crystal is known as ………..
(a) Schottky defect
(b) F center
(c) Frenkel defect
(d) non-stoichiometric defect
Answer:
(c) Frenkel defect

Question 23.
Assertion – due to Frenkel defect, density of the crystalline solid decreases.
Reason – in Frenkel defect cation and anion leaves the crystal.
(a) Both assertion and reason are true and reason is the correct explanation of assertion.
(b) 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 24.
The crystal with a metal deficiency defect is ………..
(a) NaCI
(b) FeO
(c) ZnO
(a) KCI
Answer:
(b) FeO

Question 25.
A two dimensional solid pattern formed by two different atoms X and Y is shown below. The black and white squares represent atoms X and Y respectively. The simplest formula for the compound based on the unit cell from the pattern is ………..

(a) XY₈
(b) X₄Y₉
(c) XY₂
(d) XY₄
Answer:
(a) XY₈

II. Answer the following questions:

Question 1.
Define unit cell.
Answer:
A basic repeating structural unit of a crystalline solid is called a unit ccli.

Question 2.
Cive any three characteristics of ionic crystals.
Answer:

1. Ionic solids have high melting points.
2. These solids do not conduct electricity, because the ions are fixed in their lattice positions.
3. They do conduct electricity in molten state (or) when dissolved in water because, the ions are free to move in the molten state or solution.

Question 3.
Differentiate crystalline solids and amorphous solids.
Answer:
Crystalline solids:

1. Long range orderly arrangement of constituents
2. Definite shape
3. Generally crystalline solids are anisotropic in nature
4. They are true solids
5. Definite Heat of fusion
6. They have sharp melting points.
7. Examples: NaCl, diamond etc.,

Amorphous solids:

1. Short range, random arrangement of constituents
2. Irregular shape
3. They are isotropic like liquids
4. They are considered as pseudo solids (or) super cooled liquids
5. Heat of fusion is not definite
6. Gradually soften over a range of temperature and so can be moulded.
7. Examples: Rubber , plastics, glass etc

Question 4.
Classify the following solids.

1. P₄
2. Brass
3. Diamond
4. NaCI
5. iodine

Answer:

1. P₄ – Molecular solid
2. Brass – Metallic solid
3. Diamond –
4. NaCl – Ionic solid
5. Iodine – Molecular solid

Question 5.
Explain briefly seven types of unit cell.
Answer:
Seven types of unit cell:

1. Cubic – NaCl
2.  Tetragonal – TiO₂
3. Orthorhombic – BaSO₄
4. Hexagonal – ZnO
5. Monoclinic – PbCrO₄
6. Triclinic – H₃BO₃
7. Rhombohedral – Cinnabar Cubic

They differ in the arrangements of their crystallographic axes and angles. Corresponding to the above seven, Bravis defined 14 possible crystal system as shown in the figure.

Question 6.
Distinguish between hexagonal close packing and cubic close packing.
Answer:
Hexagonal close packing

1. aba arrangement
2. In this case, the spheres of the third layer are exactly aligned with those of the first layer
3. In HCP, tetrahedral voids of the second layer may be covered by the spheres of the third layer

Cubic close packing:

1. abc arrangement
2. In this case, the spheres of the third layer are not aligned with those of the first layer or second layer. Only when fourth layer is placed, its spheres are aligned with the first layer
3. In cep third layer may be placed above the second layer in a manner such that its sphere cover the octahedral voids

Question 7.
Distinguish tetrahedral and octahedral voids.
Answer:
Tetrahedral void

1. A single triangular void in a crystal is surrounded by four (4) spheres and is called a tetrahedral void
2. A sphere of second layer is above the void of the first layer, a tetrahedral void is formed
3. This constitutes four spheres, three in the lower and one in upper layer. When the centres of these four spheres are joined a tetrahedron is formed
4. The radius of the sphere which can be accommodated in an octahedral hole without disturbing the structure should not exceed 0.414 times that of the structure forming sphere
5. Radius of an tetrahedral void \(\frac { r }{ R }\) = 0.225

Octahedral void

1. A double triangular void like c is surrounded by six(6) spheres and is called an octahedral void
2. The voids in the first layer are partially covered by the spheres of layer now such a void is called a octahedral void
3. This constitutes six spheres, three in the lower layer and three in the upper layer. When the centers of these six spheres are joined an octahedron is formed
4. The sphere which can be placed in a tetrahedral hole without disturbing the close packed structure should not have a radius larger than 0.225 times the radius of the sphere forming the structure
5. Radius of a octahedral void \(\frac { r }{ R } \) = 0.414

Question 8.
What are point defects?
Answer:
If the deviation occurs due to missing atoms, displaced atoms or extra atoms the imperfection is named as a point defect. Such defects arise due to imperfect packing during the original crystallisation or they may arise from thermal vibrations of atoms at elevated temperatures.

Question 9.
Explain Schottky defect.
Answer:
Schottky defect arises due to the missing of equal number of cations and anions from the crystal lattice. This effect does not change the stoichiometry of the crystal.Ionic solids in which the cation and anion are of almost of similar size show schottky defect.
Example: NaCl.

Presence of large number of schottky defects in a crystal, lowers its density. For example, the theoretical density of vanadium monoxide (VO) calculated using the edge length of the unit cell is 6.5 g cm^-3 but the actual experimental density is 5.6 gcm³. It indicates that there is approximately 14% Schottky defect in VO crystal. Presence of Schottky defect in the crystal provides a simple way by which atoms or ions can move within the crystal lattice.

Question 10.
Write short note on metal excess and metal deficiency defect with an example. Metal excess defect.
Answer:
Metal excess defect arises due to the presence of more number of metal ions as compared to anions.Alkali metal halides NaCl, KCl show this type of defect.The electrical neutrality of the crystal can be maintained by the presence of anionic vacancies equal to the excess metal ions (or) by the presence of extra cation and electron present in interstitial position.

For example, when NaCl crystals are heated in the presence of sodium vapour, Na⁺ ions are formed and are deposited on the surface of the crystal. Chloride ions (Cl^–) diffuse to the surface from the lattice point and combines with Na⁺ ion.

The electron lost by the sodium vapour diffuse into the crystal lattice and occupies the vacancy created by the Cl^– ions. Such anionic vacancies which are occupied by unpaired electrons are called F centers. Hence, the formula of NaCl which contains excess Na⁺ ions can be written as Na_1+xCl.

Metal deficiency defect:
Metal deficiency defect arises due to the presence of less number of cations than the anions. This defect is observed in a crystal in which, the cations have variable oxidation states. For example, in FeO crystal, some of the Fe²⁺ ions are missing from the crystal lattice.

To maintain the electrical neutrality, twice the number of other Fe²⁺ ions in the crystal is oxidized to Fe³⁺ ions. In such cases, overall number of Fe²⁺ and Fe³⁺ ions is less than the O^2- ions. It was experimentally found that the general formula of ferrous oxide is Fe_xO, where x ranges from 0.93 to 0.98.

Question 11.
Calculate the number of atoms in a fee unit cell.
Answer:
Number of atoms in a fee unit cell,
= \(\frac { { N }_{ c } }{ 8 }\) + \(\frac { { N }_{ f } }{ 2 }\)
= \(\frac { 8 }{ 8 } \) + \(\frac { 6 }{ 2 } \) = 1 + 3 = 4

Question 12.
Explain AAAA and ABABA and ABCABC type of three dimensional packing with the help of neat diagram.
Answer:
1. AAAA type of three dimensional packing
This type of three dimensional packing arrangements can be obtained by repeating the AAAA type two dimensional arrangements in three dimensions, i.e., spheres in one layer sitting directly on the top of those in the previous layer so that all layers are identical.

All spheres of different layers of crystal are perfectly aligned horizontally and also vertically, so that any unit cell of such arrangement as simple cubic structure as shown in fig.

In simple cubic packing, each sphere is in contact with 6 neighbouring spheres – Four in its own layer, one above and one below and hence the coordination number of the sphere in simple cubic arrangement is 6.

2. ABABA type of three dimensional packing:
In this arrangement, the spheres in the first layer (A type) are slightly separated and the second layer is formed by arranging the spheres in the depressions between the spheres in layer A as shown in figure.

The third layer is a repeat of the first. This pattern ABABAB is repeated throughout the crystal. In this arrangement, each sphere has a coordination number of 8, four neighbors in the layer above and four in the layer below.

3. ABCABC type of three dimensional packing:
In this arrangement (FCC) second layer spheres are arranged at the dips of first layer. Third layer spheres are arranged in a manner such that it cover the octahedral void. Then no longer third layer is similar to first or second layer.

Third layer gives different arrangement. Fourth layer spheres are similar to first layer. If the first, second and third layer are represented as A,B,C then this type of packing gives the arrangement of layers as ABCABC… (i.e.,), the first three layers do not resemble first, second and third layers respectively and the sequence is repeated.

with the addition of more layers. In this arrangement atoms occupy 74% of the available space and thus has 26% vacant space. The coordination number is 12. Voids – The empty spaces between the three dimensional layers are known as voids. There are two types of common voids possible. They are tetrahedral and octahedral voids.

Tetrahedral void – A void formed by three spheres of a layer in contact with each other and also with a sphere on the top or bottom layer is a hole between four spheres. The spheres are arranged at the vertices of a regular tetrahedron such a hole or void is called tetrahedral void.

Octahedral void:
A hole or void formed by three spheres of a hexagonal layer and another three spheres of the adjacent layer is a hole between six spheres. The spheres are arranged at the vertices of a regular octahedron. Such a hole or void is abc arrangement – ccp structure called octahedral void.

Question 13.
Why ionic crystals are hard and brittle?
Answer:
The ionic compounds are very hard and brittle. In ionic compounds the ions are rigidly held in a lattice because the positive and negative ions are strongly attracted to each other and difficult to separate. But the brittleness of a compound is now easy to shift the position of atoms or ions in a lattice.

If we apply a pressure on the ionic compounds the layers shifts slightly. The same charged ions in the lattice comes closer. A repulsive forces arises between ‘ same charged ions, due to this repulsions the lattice structure breaks down chemical bonding.

Question 14.
Calculate the percentage efficiency of packing in case of body centered cubic crystal. Packing efficiency.
Answer:
In body centered cubic arrangement the spheres are touching along the leading diagonal of the cube as shown in the In ∆ABC,

AC² = AB² + BC²
AC = \(g\sqrt { { AB }^{ 2 }+{ BC }^{ 2 } }\)
AC = \(g\sqrt { { a }^{ 2 }+{ a }^{ 2 } }\) = a²
In ∆ACG,
AG² = AC² + CG²
AG =\(g\sqrt { { AC }^{ 2 }+{ CG }^{ 2 } }\)
AG = \(\sqrt { { \left( \sqrt { 2 } a \right) }^{ 2 }+{ a }^{ 2 } }\)
AG = \(g\sqrt { { 2a }^{ 2 }+a^{ 2 } }\) = \(g\sqrt { 3a^{ 2 } } \) = \(\sqrt { 3 } a\)
i.e., \(g\sqrt { 3 } \)a = 4r
r = \(\frac { \sqrt { 3 } }{ 4 } a\)
∴ Volume of the sphere with radius ‘r’
= \(\frac { 4 }{ 3 } \) πr³
= \(\frac { 4 }{ 3 } \) π \(\left( \frac { \sqrt { 3 } }{ 4 } a \right)\)
= \(\frac { \sqrt { 3 } }{ 6 }\) πa³
Number of spheres belong to a unit cell in bee arrangement is equal to two and hence the total volume of all spheres

i.e., 68% of the available volume is occupied.The available space is used more efficiently than in simple cubic packing

Question 15.
What is the two dimensional coordination number of a molecule in square close packed layer?
Answer:
Square close packing – When the spheres of the second row are placed exactly above those of the first row. This way the spheres are aligned horizontally as well as vertically. The arrangement is AAA type. Coordination number is 4.

Question 16.
Experiment shows that Nickel oxide has the formula Ni_0.96 O_1.00. What fraction of Nickel exists as of Ni²⁺ and Ni³⁺ ions ?
Answer:
Let the number of Ni²⁺. Then the number of Ni³⁺ ion will be = (0.96 – x). Total number of cation, = 2 x + 3 (0.96 – x)
= 2x + 2.88 – 3x
= ( – x) + 2.88
Number of anions O2- ( – 2) x 1 = -2. Number of cations = Number of anions
– x + 2.88 2
– x = – 2.88 + 2
x =0.88
%of Ni as Ni² =\(\frac { 0.08 }{ 0.96 } \times 100\) = 91.66%
Number of Ni³⁺ ion will be = 0.96 – x
= 0.96 – 0.88 = 0.08
% of Ni as Ni³⁺ = \(\frac { 0.08 }{ 0.96 } \times 100\) = 8.3 %

Question 17.
What is meant by the term “coordination number”? What is the coordination number of atoms in a bcc structure?
Answer:

1. Coordination number – The number of nearest neighbours that surrounding a particle in a crystal is called the coordination number of that particle.
2. Coordination number of atoms in a bcc structure is 8

Question 18.
An element has bcc structure with a cell edge of 288 pm. the density of the element is 7.2 gcm^-3. How many atoms are present ¡n 208g of the element.
Answer:
An elemeñt has bec structure with a cell edge of 288 pm. The density of the element is 7.2 gcm^-3. For the Bec structure, n = 2

By mole concept, 51.42 g of the element contains 6.023 x 10²³ atom 208 g of the element will contain
= \(\frac { 6.023\times { 10 }^{ 23 }\times 208 }{ 51.42 }\) atoms
= 24.17 x 10²³ atoms (or) 2.417 x 10²⁴ atoms

Question 19.
Aluminium crystallizes in a cubic close packed structure. Its metallic radius is 125pm. Calculate the edge length of unit cell.
Answer:
Given, Radius (r) = 125 pm
Edge length of unit cell (a) = ?
Since aluminium crystallizes in Face centered cubic
r= \(\frac { a\sqrt { 2 } }{ 4 } \) (or) r=\(\frac { a }{ 2\sqrt { 2 } } \)
a = r x 2 x \(g\sqrt { 2 } \)
= 125 x 2 x 1.414
a = 353.5 pm

Question 20.
If NaCI is doped with 10² mol percentage of strontium chloride, what is the concentration of cation vacancy?
Answer:
We know that two Na⁺ ions are replaced by each of the Sr²⁺ ions while SrCl², is doped with NaCI. But in this case, only one lattice point is occupied by each of the Sr²⁺ ions and produce one cation vacancy.

Here 10^-2 mole of SrCI₂, is doped with 100 moIes of NaCI. Thus, cation vacancies produced by NaCi = 10^-2 mol. Since, 100 moles of NaCl produces cation vacancies after doping = 10^-2 mol. Therefore, I mole of NaCl will produce cation vacancies after doping

= \(\frac { { 10 }^{ -2 } }{ 100 }\)= 10^-4mol
:. Total cationic vacancies,
= 10^-4 x Avogadro’s number
= 10 x 6.023 x 10²³
= 6.023 x 10¹⁹ vacancies

Question 21.
KF crystallizes in fcc structure like sodium chloride, calculate the distance between K⁺ and F^– in KF. (given : density of KF is 2.48 g cm^-3)
Answer:
Density of KF 2.48 g cm^-3

Question 22.
An atom crystallizes ¡n fcc crystal lattice and has a density of 10 gcm3 with unit cell edge length of 100pm. calculate the number of atoms present in 1 g of crystal.
Answer:
Given, Density = 10 g cm^-3
mass = 1 g
Edge length of unit cell = 100 pm

= 0.1 cm³
Volume of unit cell = a³
= (100 x 10^-10cm)³
= 1 x 10^-24 cm³
Number of unit cell in 1 g of crystal,

The given unit cell is of FCC type. Therefore. it contains 4 atoms.
0.1 x 10²⁴ unit cells will contain 4 x 0.1 x 10²⁴ = 4 x 10²³atoms

Question 23.
Atoms X and Y form bcc crystalline structure. Atom X is present at the corners of the cube and Y is at the centre of the cube. What is the formula of the compound?
Answer:
Atoms X and Y form bcc crystalline structure. Atom X is present at the corners of the cube Atom Y is present at the centre of the cube.
No of atoms of X in the unit cell = \(\frac { { N }_{ c } }{ 8 }\) = \(\frac { 8 }{ 8 } \) = 1
No of atoms of Y in the unit cell = \(\frac { { N }_{ b } }{ 1 } \) = \(\frac { 1 }{ 1 } \) = 1
Ratio of atoms X : Y = 1 : 1
Hence formula of the compound = XY.

Question 24.
Sodium metal crystallizes in bcc structure with the edge length of the unit cell 4.3 x 10^-8 cm. Calculate the radius of sodium atom.
Answer:
Edge length of the unit cell (a) = 4.3 x 10^-8cm
Radius of sodium atom (r) = ?
For bcc structure, r = \(\frac { \sqrt { 3 } }{ 4 } a\)
= \(\frac { \sqrt { 3 } }{ 4 } a\) (4.3 x 10^-8cm)
\(\frac { 1.732\times 4.3\times { 10 }^{ -8 } }{ 4 }\)
= \(\frac { 1.732 }{ 4 } \times { 10 }^{ -8 }cm\)
= 1.86 x 10^-8 cm = l.86Å

Question 25.
Write a note on Frenkel defect.
Answer:
Frenkel defect arises due to the dislocation of ions from its crystal lattice. The ion which is missing from the lattice point occupies an interstitial position. This defect is shown by ionic solids in which cation and anion differ in size.

Unlike Schottky defect, this defect does not affect the density of the crystal. For example AgBr, in this casc, small Ag ion leaves its normal site and occupies an interstitial position as shown in the figure.

Samacheer Kalvi 12th Chemistry Solid State Evaluate Yourself

Question 1.
An element has a face centered cubic unit cell with a length of 352.4 pm along an edge. The density of the element is 8.9 gcm^-3. How many atoms are present in loo g of an element?
Answer:
Mass = 100g
Density = 8.9 g cm^-3
Edge length = 352.4 pm
(a) 352.4 x 10^-10cm
Volume of the unit cell,
a³ = (352.4 x 10¹⁰cm) 34.37 x 10²³ cm³
Volume of 100 g of an element.

Therefore number of unit cells,
\(\frac { 11.23 }{ 4.37\times { 10 }^{ -23 } }\) = 11.23 = 2.56 x 10²³
Since each Fcc cube contains 4 atoms, therefore total number of atoms in 100 g.
= 4 x (2.56 x 10²³) = 10.24 x 10²³ atoms

Question 2.
Determine the density of CsCl which crystallizes in a bcc type structure with an edge length 412.1 pm.
Answer:
Molar mass of cscl = 168.5 g /mol
Number atoms present in per unit cell for bcc (cscl)
n = 1
Edge length (a) = 412.1 pm
Density (ρ) = ?
ρ = \(\frac { nM }{ { a }^{ 3 }{ N }_{ A } }\)

Question 3.
A face centered cubic solid of an element (atomic mass 60) has a cube edge of 4 Å. Calculate its density.
For FCC unit cell n = 4
Edge length (a) = 4Å = 4 x 10^-8cm
Mass (M) = 60 g mol^-1
Density (p) = ?
ρ = \(\frac { nM }{ { a }^{ 3 }{ N }_{ A } }\)

Samacheer Kalvi 12th Chemistry Solid State Additional Questions

Samacheer Kalvi 12th Chemistry Solid State 1 Mark Questions and Answers

I. Choose the best answer.

Question 1.
Consider the following statements
(i) Solids have definite volume and shape
(ii) Solids are rigid and compressible
(iii) Solids have weak cohesive forces

Which of the above statemetns is / are not correct?
(a) (i) only
(b) (ii) & (iii) only
(c) (iii) only
(d) (i) & (ii) only
Answer:
(b) (ii) & (iii) only

Question 2.
Which one of the following is an ionic crystal?
(a) Glass
(b) Rubber
(c) NaCl
(d) SiO₂
Answer:
(c) NaCl

Question 3.
Which one of the following is an amorphous solid?
(a) Glass
(b) SiO₂
(c) NaCl
(d) Na
Answer:
(a) Glass

Question 4.
Which one of the following is an example for molecular crystals?
(a) Diamond
(b) Silica
(c) Glass
(d) Naphthalene
Answer:
(d) Naphthalene

Question 5.
Which one of the following is an example for atomic solids?
(a) Frozen elements of group 18
(b) Group 17 elements
(c) Inner – transition elements
(d) chalcogens
Answer:
(a) Frozen elements of group 18

Question 6.
Which one of the following is a covalent crystal?
(a) Glass
(b) Diamond
(c) Anthracene
(d) Glucose
Answer:
(b) Diamond

Questions 7.
Consider the following statements.
(i) Crystalline solids have irregular shape
(ii) Generally crystalline solids are anisotropic in nature
(iii) Heat of fusion of crystalline solids are not definite

Which of the above statements is / are correct?
(a) (i) & (iii)
(b) (i) only
(c) (iii) only
(d) (ii) only
Answer:
(d) (ii) only

Question 8.
Consider the following statements.
(i) Amorphous solids are isotropic like liquids
(ii) Amorphous solids are considered as pseudo solids
(iii) Amorphous solids have sharp melting points

Which of the above statemetns is / are correct?
(a) (i) only
(b) (ii) only
(c) (i) & (ii)
(d) (i) & (iii)
Answer:
(c) (i) & (ii)

Question 9.
In an ionic crystal, both cations and anions are bound together by ………..
(a) Strong electrostatic attractive forces
(b) Weak electrostatic attractive forces
(c) Vanderwaals forces of attraction
(d) Weak cohesive forces
Answer:
(a) Strong electrostatic attractive forces

Question 10.
Molecular solids contains neutral molecules held together by ………..
(a) strong cohesive forces
(b) weak vanderwaals forces
(c) weak ionic forces
(d) strong electrostatic forces
Answer:
(b) weak vanderwaals forces

Question 11.
Which is used inside pencils and in many lubricants?
(a) Lead nitrate
(b) charcoal
(c) graphite
(d) coke
Answer:
(c) graphite

Question 12.
In non polar molecular solids, molecules are held together by ………..
(a) London forces
(b) weak vanderwaals forces
(c) Strong electrostatic forces
(d) strong cohesive forces
Answer:
(a) London forces

Question 13.
Which one of the following is non-polar molecular solids?
(a) Diamond
(b) SiC
(c) Anthracene
(d) Glass
Answer:
(c) Anthracene

Question 14.
Silicon carbide is an example of ………..
(a) Ionic solid
(b) Covalent solid
(c) Polar molecular solid
(d) Non – polar molecular solid
Answer:
(b) Covalent solid

Question 15.
Naphthalene is an example of ………..
(a) ionic solid
(b) covalent solid
(c) non polar molecular solid
(d) polar molecular solid
Answer:
(c) non polar molecular solid

Question 16.
Solid NH₃ solid CO₂ are examples of ………..
(a) Covalent solids
(b) polar molecular solids
(c) molecular solids
(d) ionic solids
Answer:
(b) polar molecular solids

Question 17.
Solids ice, glucose are examples of ………..
(a) metallic solids
(b) ionic solids
(c) hydrogen bonded molecular solids
(d) non polar molecular solids
Answer:
(c) hydrogen bonded molecular solids

Question 18.
Consider the following statements.
(i) metallic solids possess high electrical and thermal conductivity
(ii) solid ice are soft solids under room temperature
(iii) In non polar molecular solids constituent molecules are held together by strong electrostatic forces of attraction

Which of the above statements is / are not correct?
(a) (i) & (ii)only
(b) (iii) only
(c) (ii) only
(d) (i) only
Answer:
(b) (iii) only

Question 19.
Each atom in the comer of the cubic unit cell is shared by how many unit cells?
(a) 8
(b) 6
(c) 1
(d) 12
Answer:
(a) 8

Question 20.
Which is the coordination number of each atom in a simple cubic unit cell?
(a) 8
(b) 6
(c) 12
(d) 4
Answer:
(b) 6

Question 21.
The number of atoms belongs to fcc unit cell is ………..
(a) 2
(b) 4
(c) 6
(d) 12
Answer:
(a) 2

Question 22.
The number of atoms in fee unit cell is ………..
(a) 2
(b) 4
(c) 6
(d) 8
Answer:
(b) 4

Question 23.
The atoms the face centre is being shared by ………..
(a) 4
(b) 8
(c) 2
(d) 6
Answer:
(c) 2

Question 24.
An atom present at the body centre be longs to only unit cell ………..
(a) 1
(b) 2
(c) 4
(d) 8
Answer:
(a) 1

Question 25.
Which one of the following is known as Bragg’s equation’?
(a) d = \(\frac { 2sinθ }{ nλ } \)
(b) d = \(\frac { nλ }{ 2sinθ } \)
(c) d = \(\frac { d }{ sinθ } \)
(d) d = \(\frac { 2sinθ }{ nλ } \)
Answer:
(b) d = \(\frac { nλ }{ 2sinθ } \)

Question 26.
Which one of the following formula is used to calculate the density of the unit cell ?
(a) ρ = \(\frac { nM }{ { a }^{ 3 }{ N }_{ A } } \)
(b) ρ = \(\frac { { a }^{ 3 }{ N }_{ A } }{ nM } \)
(c) ρ = \(\frac { { N }_{ A } }{ { a }^{ 3 }{ N }M } \)
(d) ρ = \(\frac { { a }^{ 3 }{ N }_{ A } }{ n } \)
Answer:
(a) ρ = \(\frac { nM }{ { a }^{ 3 }{ N }_{ A } } \)

Question 27.
Which is the packing fraction in simple cubic unit cell?
(a) 52.31%
(b) 100%
(c) 68%
(d) 75%
Answer:
(a) 52.3 1%

Question 28.
The packing fraction in bcc arrangement is ………..
(a) 52.3 1%
(b) 68%
(c) 100%
(d) 80%
Answer:
(b) 68%

Question 29.
Which is the coordination number in both hep and ccp arrangements?
(a) 12
(b) 6
(c) 4
(d) 8
Answer:
(a) 12

Question 30.
What is the coordination number of B₂O₃?
(a) 4
(b) 6
(c) 8
(d) 3
Answer:
(d) 3

Question 31.
Which one of the following is the structure of B₂O₃ ?
(a) Tetra hedral
(b) Octahedral
(c) Trigonal planar
(d) Cubic
Answer:
(c) Trigonal planar

Question 32.
The coordination number of zinc sulphide is ………..
(a) 3
(b) 4
(c) 6
(d) 8
Answer:
(b) 4

Question 33.
The coordination number of CSCI ¡s ………..
(a) 3
(b) 4
(c) 6
(d) 8
Answer:
(d) 8

Question 34.
Which one of the following is the coordination number of NaCl?
(a) 3
(b) 4
(c) 6
(d) 8
Answer:
(c) 6

Question 35.
Which one of the following is the packing efficiency in fcc unit cell?
(a) 74%
(b) 52.6 1%
(c) 100%
(d) 68%
Answer:
(a) 74%

Question 36.
Which one of the following is an example for schoriky defect?
(a) NaCI
(b) AgBr
(c) KCI
(d) FeS
Answer:
(a) NaCl

Question 37.
Which one of the following is an example for Frenkel defect?
(a) NaCl
(b) AgCI
(c) AgBr
(d) AgNO₃
Answer:
(c) AgBr

Question 38.
Metal excess defect is possible in ………..
(a) AgCI
(b) AgBr
(c) KCl
(d) Fes
Answer:
(c) KCl

Question 39.
Which one of the following is the metal deficiency defect?
(a) FeO
(b) ZnO
(c) KCl
(d) NaCl
Answer:
(a) FeO

Question 40.
Which one of the following shows non- stoichiometric defect?
(a) FeO
(b) AgBr
(c) ZnO
(d) Both a and c
Answer:
(d) Both a and c

II. Fill in the blanks

1. Naphthalene,Anthracene and glucose are examples of ……………
2. The best examples of covalent crystals are …………… and ……………
3. Frozen elements of group 18 are called ……………
4. Glass, Rubber, plastics are the examples of …………… solids.
5. …………… means uniformity in all directions.
6. Crystalline solids are …………… and they show different values of physical properties when measured along different directions.
7. NaCl and KCl are the examples of …………… crystals.
8. Diamond and silicon carbide are the examples of …………… solids.
9. In molecular solids, the neutral molecules are held together by weak ……………
10. …………… is a component of many lubricants for example cycle chain oil.
11. In non polar molecular solids constituent molecules are held together by ……………
12. In solids CO₂ solid NH₃ the molecules are held together by strong ……………
13. Glucose and urea are generally …………… under room temperature.
14. …………… solids possess excellent electrical and thermal conductivity.
15. The regular arrangement of the ions throughout the crystal is called a ……………
16. The basic repeating structural unit of a crystalline solid is called a ……………
17. The number of the nearest neighbours that surrounding a particle in a crystal is called the ……………
18. A unit cell that contains only one lattice point is called a ……………
19. There are …………… primitive crystal systems.
20. The coordination number of bcc is ……………
21. Each atom in the comer of cubic unit cell is shared by …………… neighbouring unit cells.
22. The number of atoms in bcc unit cell is ……………
23. The number of atoms in a fee unit cell is ……………
24. …………… is the most powerful tool for the determinaiton of crystal structure.
25. Only …………… of the available volume is occupied by the spheres in simple cubic packing
26. Of all the metals in the periodic table, only …………… crystallizes in simple cubic pattern.
27. In bcc cubic pattern …………… of the available volume is occupied.
28. If the third layer arrangement is aba arrangement, it is called …………… arrangement.
29. If third layer arrangement is abc arrangment, it is known as …………… arrangement.
30. In both …………… and …………… arrangements, the coordination number of each sphere is 12.
31. The packing efficiency of fee unit cell is ……………
32. …………… defect arises due to the missing of equal number of cations and anions from the crystal lattice.
33. Presence of large number of schottky defects in a crystal, lowers its ……………
34. Vanadium monoxide shows …………… defect.
35. …………… arises due to the dislocation of ions from its crystal lattice.
36. …………… arises due to the presence of more number of metalions as compared to anions.
37. Zno is …………… at room temperature but when it is heated it becomes in colour.
38. …………… arises due to the presence of less number of cations than the anions.
39. …………… is the appearance of an electrical potential across the sides of the crystal, when it is subjected to mechanical stress.
40. Stoichiometric defects in an ionic solid is also called …………… or …………… defect.

Answer:

1. Molecular crystals
2. Diamond, SiO₂
3. Atomic solids
4. Amorphous
5. Isotropy
6. Anisotropic
7. Ioni
8. Covalent
9. Vander waals forces
10. Graphite
11. London forces
12. dipole-dipole interactions
13. Soft solids
14. Metallic
15. Crystal lattice
16. Unit cell
17. Coordination number
18. Primitive unit cell
19. Seven
20. Eight
21. Eight
22. Two
23. Four
24. X-ray diffraction analysis
25. 52.31%
26. Polonium
27. 68%
28. hep or hexagonal close packed
29. ccp or cubic close packed
30. hep, ccp
31. 74%
32. Schottky
33. density
34. Schottky defect
35. Frenkel defect
36. metal excess defect
37. Colourless, yellow
38. Metal deficiency
39. Piezoelectricity
40. intrinsic or thermodynamic

III. Match the following:

Question 1.

Answer:
(a) 3, 4, 1, 2

Question 2.

Answer:
Answer:
(b) 3, 1, 4, 2

Question 3.

Answer:
(a) 2, 4, 1, 3

Question 4.

Answer:
(b) 3, 1, 4, 2

Question 5.

Answer:
(c) 4, 1, 2, 3

IV. Assertion and Reason

Question 1.
Assertion (A): Amorphous solids are isotropic in nature.
Reason (R): In amorphous solids, they have identical values of physical properties such as refractive index, electrical conductance in all directions which is called isotropy.
(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): Crystalline solids are anisotropic in nature.
Reason (R): Anisotropy is the property which depends on the direction of measurement. Crystalline solids are anisotropic and they show different values of physical properties when measured along different directions.
(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 3.
Assertion (A): Ionic solids do not conduct electricity in solid state but in molten state they conduct electricity.
Reason (R): In solid state, the ions are fixed in their lattice positions but in molten state, the ions are free to move and conduct electricity.
(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:
(A)Both A and R are correct and R is the correct explanation of A

Question 4.
Assertion (A): Diamond and Silicon carbide are very hard and have high melting point.
Reason (R): In covalent solids, the atoms are bound together in a three dimensional network entirely by covalent bonds.
(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): Solid CO₂ Solid NH₃ have higher melting points.
Reason (R): The constituents are molecules formed by polar covalent bonds. They are held together by relatively strong dipole- dipole interactions.
(a) A is correct but R is wrong.
(b) A is wrong but R is correct
(c) A and R are correct and R is the correct explanation of A
(d) A and R are correct but R is not the correct explanation of A
Answer:
(c) A and R are correct and R is the correct explanation of A

Question 6.
Assertion (A): Solid ice, Glucose are generally soft solids under room temperature.
Reason (R): The constituents are held together by strong electrostatic forces of attraction.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are correct and 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:
(c) A is correct but R is wrong.

Question 7.
Assertion (A): In bcc, the available volume is more efficiently used than in simple cubic packing.
Reason (R): In simple cubic arrangement, the number of spheres belongs to a unit cell is equal to one whereas in bcc, it is equal to 2.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are correct 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 8.
Assertion (A): B₂ O₃ has trigonal planar structure.
Reason (R): The ratio of radius of cation and anion \(\frac { { r }_{ { c }^{ + } } }{ { r }_{ { A }^{ – } } } \) = 0.155 – 0.225 plays an important role in determining the structure . and B₂ O₃ has coordination number as 3 and has trigonal planar structure.
(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): Schottky defect does not change the stoichiometry of the crystal.
Reason (R): This defect arises due to the missing of equal number of cations and anions from the crystal lattice.
(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:
(a) Both A and R are correct and R is the correct explanation of A

Question 10.
Assertion (A): Zinc oxide is colourless at room temperature but on heating it becomes yellow in colour.
Reason (R): On heating Zinc loses oxygen and thereby forming free zn²⁺ ions. The excess zn²⁺ ions move to interstitial sites and the electrons also occupy interstitial positions.
(a) Both A and R are correct and R is the correct explanation of A
(b) Both A and R are correct 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

V. Find the odd one out

Question 1.
(a) Plastic
(b) Rubber
(c) Glucose
(d) Glass
Answer:
(c) Glucose It is a molecular solid where as others are amorphous solids.

Question 2.
(a) Anthracene
(b) Naphthalene
(c) Glucose
(d) Sodium chloride
Answer:
(d) Sodium chloride It is ionic crystall where as others are molecular crystals.

Question 3.
(a) Sodium
(b) Pottasium
(c) Frozen elements of group 18
(d) Gold
Answer:
(c) Frozen elements of group 18 It is atomic solid where as others are metallic solids.

Question 4.
(a) Solid CO₂
(b) Solid ice
(c) Glucose
(d) Urea
Answer:
(a) Solid CO₂ It is a polar molecular solid where as others are hydrogen bonded molecular solids.

Question 5
(a) Cubic
(b) Rhombohedral
(c) Hexagonal
(d) Cyclic
Answer:
(d) Cyclic It is a ring structure where as other primitive crystal systems.

VI. Find the odd correct pair

Question 1.
(a) Glass, plastic
(b) Rubber, ice
(c) Nacl, Glucose
(d) Urea, solid NH₃
Answer:
(a) Glass, plastic (Amorphous solids)

Question 2.
(a) NaCI, KCI
(b) FeO, ZnO
(e) AgBr, AgNO₃
(d) VO, ZnO
Answer:
(a) Naci, Kcl (schottky defect)

Question 3.
(a) Solid CO₂ Solid ice
(b) Solid CO₂ Solid NH₃
(c) Graphite, Silicon carbide
(d) Naphthalene, Phenol
Answer:
(b) Solid CO₂ Solid NH₃ Polar molecular solids

Question 4.
(a) NaCI, SiC
(b) Naphthalene, anthracene
(c) Solid ice, graphite
(d) Copper, KO
Answer:
(b) Naphthalcne, anthracenc – It is non-polar molecular solid examples.

VII. Find out the odd incorrect pair

Question 1.
(a) NaCl, KCl
(b) Naphthalenc, anthracene
(c) Solid CO₂, Solid NH₃
(d) Diamond, solid ice
Answer:
(d)Diamond, solid ice

Question 2.
(a) Cu, Fc
(b) Glucose, Urca
(c) Diamond, SiC
(d) Benzene, glucose
Answer:
(d) Benzene, glucose

Samacheer Kalvi 12th Chemistry Solid State 2 Mark Question and Answers

Question 1.
What are crystalline solid? Give example.
Answer:
A crystalline solid is one in which its constituents (atoms, ions or molecules) have an orderly arrangement extending over a long range which has three dimensional pattern. Example – NaCl.

Question 2.
What are amorphous solid? Give example.
Answer:
In an amorphous solid, the constituents are randomly arranged. It is a short range arrangement of constituents. Eg – Glass.

Question 3.
What are covalent solids? Give example.
Answer:
In covalent solids, the constituents (atoms) are bound together in a three dimensional network entirely by covalent bonds. Examples. Diamond, Silicon carbide.

Question 4.
Silicon carbide is very hard. Justify this statement.
Answer:
Silicon carbide is very hard. It is a covalent solid contains the atoms which are bound together in a three dimensional network entirely by covalent bonds. So the covalent network crystal SiC is very hard and have high melting point.

Question 5.
Write a note about molecular solids.
Answer:

1. In molecular solids, the constituents are neutral molecules. They are held together by weak vander waals forces.
2. Molecular solids are soft and they do not conduct electricity. Eg – Solid CO₂

Question 6.
What are non-polar molecular solids? Give example.
Answer:

1. In non polar molecular solids, constituent molecules are held together by weak dispersion forces or London forces.
2. They have low melting points and are usually in liquids or gaseous state at room temperature. Eg., Naphthalene, anthrancene.

Question 7.
What are hydrogen bonded molecular solids? Give example.
Answer:

1. Molecular solids in which the constituents are held together by hydrogen bonds.
2. They are generally soft solids under room temperature. Examples., Solid ice, Glucose, Urea.

Question 8.
Define crystal lattice.
Answer:
The regular arrangement of these species throughout the crystal is called a crystal lattice.

Question 9.
Define coordination number.
Answer:

1. A crystal may be considered to consist of large number of unit cells, each one in direct contact with its nearer neighbour and all similarly oriented in space.
2. The number of the nearest neighbours that surrounding a particle in a crystal is called coordination number of that particle.

Question 10.
Draw the tetragonal crystal systems.
Answer:

Question 11.
Draw the hexagonal primitive crystal structure.
Answer:

Question 12.
Draw the typec of monoclinic primitive cubic crystals.
Answer:

Question 13.
Draw the primitive cubes.

1. trigonal
2. triclinic

Answer:

Question 14.
What is Bragg’s equation?
Answer:
1. X-ray diffraction analysis is the most powerful tool fiw the determination of crystal structure.

2. The interplanar distance (d) between two successive planes of atoms can be calcuLated using the following equation form the X-ray diffraction data 2d sin θ = nλ. The equation is known as Bragg’s equation.

Where λ = wavelength of X-ray – d = Interplanar distance, θ The angle of diffraction – n = order of reflection. By knowing the values of θ, λ and n. we can calculate the value of d. d = \(\frac { nλ }{ 2Sinθ } \) Using these values, the edge of the unit cell can be calculated.

Question 15.
What is meant by linear arrangement of spheres in one direction?
Answer:
1. In a specific direction, there is only one possibility to arrange the spheres in one direction.

2. In this arrangement, each sphere is in contact with two neighbouring spheres on either.

Question 16.
What is meant by piezo electricity?
Answer:
Piezo electricity is the appearance of an electrical potential across the sides of a crystal. When you subject it to mechanical stress. The word piezo electricity means electricity resulting from pressure and latent heat. Even the inverse is possible which is known as inverse piezo electric effect.

Question 17.
Why are solids rigid?
Answer:
In a solid, the constituent particles are very closely – packed. Hence, the forces of attraction among these particles are very strong, that is why they are rigid.

Question 18.
Why do solids have a definite volume?
Answer:
The constituent particles of a solid have fixed positions and are not free to move i.e., they possess rigidity. That is why they have a definite volume.

Question 19.
Classify the following as amorphous or crystalline solids: Polyurethane, naphthalene, benzoic acid, teflon, potassium nitrate, cellophane, polyvinyl chloride, fibre glass, copper.
Answer:
Amorphous solids: Polyurethane, teflon, cellophane, polyvinyl chloride, fibre glass. Crystalline solids: Benzoic acid, naphthalene, potassium nitrate, copper.

Question 20.
Why is glass considered as super cooled liquid?
Answer:
Glass is an amorphous solid. Like liquids it has a tendency to flow, though very slowly. The proof of this fact is that glass panes in the windows or doors of old buildings are invariably found to be slightly thicker at the bottom than at the top.

Question 21.
Refractive index of a solid is observed to have the same value along all directions. Comment on the nature of this solid. Would it show cleavage property?
Answer:
As the solid has same value of refractive index along all directions, this means that it is isotropic and hence amorphous. Being an amorphous solid, it would not show a clean cleavage when cut with a knife. Instead it would break into pieces with irregular surfaces.

Question 22.
Classify the following solids in different categories based on the nature of intermolecular forces operating in them: Potassium sulphate, tin, benzene, urea, ammonia, water, zinc sulphide, graphite, rubidium, argon, silicon carbide.
Answer:

1. Potassium sulphate – Ionic
2. Tin – Metallic
3. Benzene – Molecular (non polar)
4. Urea – Molecular (polar)
5. Ammonia – Molecular (hydrogen bonded)
6. Water – Molecular (hydrogen bonded)
7. Zinc Suiphide – Ionic
8. Graphite – Covalent or Network
9. Rubidium – Metallic
10. Argon – Molecular (non polar)
11. Silicon carbide – Covalent or Network

Question 23.
Solid A is a very hard electrical insulator in solid as well as in molten state, and melts at extremely high temperature. What type of solid is it?
Answer:
Covalent or Network solid like SiO₂ (quartz) or SIC or C (diamond).

Question 24.
Ionic solids conduct electricity in molten state but not in solid state. Explain.
Answer:
In the molten state, ionic solids dissociate to give free ions and hence can conduct electricity. However in the solid state, as the ions are not free to move but remain held together by strong electrostatic forces of attraction, so they cannot conduct electricity in the solid state.

Question 25.
An element with molar mass 2.7 x 10^-2 kg mol^-1 forms a cubic unit cell with edge length 405 pm. If the density is 2.7 x 10³ kg m^-3, what ¡s the nature of the cubic unit cell?
Answer:
Density

Thus, there are 4 atoms of elements present per unit cell, hence, the cubic unit cell must be facecentred or cubic close – packed (cep).

Question 26.
Ionic solids, which have anionic vacancies due to metal excess defect develop colour. Explain with the help of suitable example.
Answer:
Taking the example of NaCl, when its crystals arc heated in presence of sodium vapour some chloride ion leave their lattice sites to combine with sodium to form NaCI. For this released diffuses into the crystal to occupy the anion vacancies created by Cl ions.

The crystal now has excess of sodium. The sites occupied by unpaired electrons are called F – centres. They impart yellow colour to the crystal because they absorb energy from the visible light and get excited.

Question 27.
Classify each of the following solids as ionic, metallic, molecular, network (covalent) or amorphous.

1. Tetra phosphorous decoxide (P₄ O₁₀)
2. Ammonium Phosphate (NH₄)₃PO₄
3. SIC
4. I₂
5. P₄
6. Plastic
7. Graphite
8. Brass
9. Rb
10. LiBr
11. Si

Answer:

1. Tetra phosphorous decoxide (P₄ O₁₀) = Molecular solid
2. Ammonium Phosphate (NH₄)₃PO₄ = Ionic solid
3. SiC = Covalent solid
4. I₂ = Molecular solid
5. P₄ = Molecular solid
6. Plastic Amorphous solid
7. Graphite = Covalent solid
8. Brass = Metallic solid
9. Rb = Metallic solid
10. LiBr = Ionic solid
11. Si = Covalent solid

Question 28.
What ¡s the formula of a compound in which the element Y forms ccp Lattice and atoms of X occupy 2/3rd of tetrahedral voids?
Answer:
Number of element Y = n, Number of element X = 2 n x \(\frac { 2 }{ 3 } \). As number of tetrahedral void = 2n
X : Y= \(\frac { 4n }{ 3 } \) : n
Formula = X₄ Y₃

Question 29.
The energy required to vapourise one mole of copper is smaller than that of energy required to vapourise I mol of diamond. Why?
Answer:
Copper is a metallic solid having metal-metal bonds while diamond is a covalent solid having covalent bonds.Metallic bonds are weaker than covalent bonds and thus less amount of energy is required to break metallic bonds than covalent bonds.

Question 30.
Assign reason for the following:

1. phosphorous doped silicon is a semiconductor.
2. Schottky defect lowers the density of a solid.

Answer:

1. It is because its conductance is intermediate between conductor and insulator.
2. In Schottky defect, both cations and anions are missing which leads to lowering the density of a solid.

Samacheer Kalvi 12th Chemistry Solid State 3 Mark Questions and Answers

Question 1.
Distinguish between isotropy and anisotropy?
Answer:
Isotropy:

1. Isotropy means uniformity in all directions.
2. Isotropy means having identical values of physical properties such as refractive index, electrical conductance in all directions.
3. Isotropy is the property of amorphous solids.

Anisotropy:

1. Anisotropy means non-uniformity in all directions.
2. Anisotropy is the property which depends on the direction of measurement. They show different values of physical properties when measured along different directions.
3. Anisotropy is the properly of crystalline solids.

Question 2.
What are polar molecular solids? Give example.
Answer:

1. The constituents are molecules formed by polar covalent bonds.
2. They are held together by relatively strong dipole-dipole interactions.
3. They have higher melting points than the non-polar molecular solids. Eg., Solid CO₂, Solid NH₃.

Question 3.
Write a note about metallic solids.
Answer:

1. In metallic solids, the lattice points are occupied by positive metal ions and a cloud of electrons pervades the space.
2. They are hard and have high melting point.
3. Metallic solids possess excellent electrical and thermal conductivity. They possess bright lustre.
4. Examples – Metals and metal alloys Cu, Fe, Zn, Ag, Ay, Cu – Zn etc.

Question 4.
What are characteristic parameters of a unit cell?
Answer:
1. A basic repeating structural unit of a crystalline solid is called a unit cell.

2. A unit cell is characterised by the three edge lengths or lattice constants a,b and c and the angle between the edges a,P and y.

3.

Question 5.
What are type of unit cells? Give their names.
Answer:

1. There are two types of unit cells, a) primitive b) Non – primitive.
2. A unit cell that contains only one lattice point is called a primitive unit cell, which is made up from the lattice points at each of the comers.
3. In the case of non-primitive unit cells, there are additional lattice points, either on a face of the unit cell or with in the unit cell.

Question 6.
Draw the seven types of primitive crystal systems.
Answer:

Question 7.
Draw the types of cubic crystal systems.
Answer:

Question 8.
Draw the types of orthorhombic cubic crystal systems.
Answer:

Question 9.
Calculate the number of atoms belong to one unit cell of simple cubic unit cell(sc).
Answer:
1. In the simple cubic unit cell, each corner is occupied by an identical atoms (or) ions (or) molecules and they touch along the edges of cube,do not touch diagonally. The coordination number of each atom is 6.

2. Each atom in the comer of the cubic unit cell is shared by 8 neighbouring unit cells and therefore atoms per unit cell is equal to \(\frac { { { N }_{ c } } }{ 8 }\). where Nc is the number of atoms at the corners.

3. no of atoms in a Sc unit cell = \(\left( \frac { { N }_{ c } }{ 8 } \right)\) = \(\left( \frac { 8 }{ 8 } \right) \) = 1

Question 10.
Calculate the number of atoms per unit cell of bec type.
Answer:
1. In a body centered cubic unit cell, each corner is occupied by an identical particle and in addition to that one atom occupied the body centre.

2. Those atoms which occupy the corners do not touch each other, however they all touch the one that occupies the body centre.

3. Hence each atom is surrounded by eight nearest neighbours and coordination number is 8. An atom present at the body centre belongs to only a particular unit cell i.e., unshared by other cell.
∴number of atoms in a bcc unit cell = \(\frac { { N }_{ c } }{ 8 }\) + \(\frac { { N }_{ b } }{ 1 }\) + \(\frac { 8 }{ 8 } \) = \(\frac { 1 }{ 1 } \) = 1 + 1 = 2

Question 11.
How will derive the formula of density of a unit cell?
Answer:
1. Using the edge length of a unit cell, we can calculate the density (p )of the crystal by considering a cubic unit cell as follows.

Substitute the value (3) in (2)
Mass of the unit cell = n x \(\frac { M }{ { N }_{ A } }\)
For a cubic unit cell, all the edge lengths are equal. i.e., a = b = c
Volume of the unit cell = a x a x a = a³
∴Density of the unit cell = ρ = \(\frac { nM }{ { a }^{ 3 }{ N }_{ A } }\)

Question 12.
Calculate the packing fraction of siniple cubic arrangement
Answer:
In a simple cubic arrangement

Consider the cube with an edge length ‘a’
Volume of the cube with edge length a is = a x a x a = a³ …………….(l)
Let ‘r’ ¡s the radius of the sphere
From the figure a = 2 r ⇒ r = \(\frac { a }{ 2 } \)
:. volume of the sphere with radius r = \(\frac { 4 }{ 3 } \) πr³
= \(\frac { 4 }{ 3 } \) π \({ \left( \frac { a }{ 2 } \right) }^{ 3 }\)
= \(\frac { 4 }{ 3 } \) π \(\left( \frac { { a }^{ 3 } }{ 8 } \right) \)
= \(\frac { { πa }^{ 3 } }{ 6 }\) ……………………….(2)

In a simple cubic arrangement. number of spheres belongs to a unit cell equal to one.
∴Total volume occupied by the spheres in sc unit cell = 1 x \(\left( \frac { { πa }^{ 3 } }{ 6 } \right) \) ……(3)
Dividing 3 by 1

Packing fraction = \(\left( \frac { \frac { \pi { a }^{ 3 } }{ 6 } }{ { a }^{ 3 } } \right) \times 100\) = \(\frac { 100π }{ 6 }\) = 52.3 1% Only 52.31% of the available volume is occupied by the spheres in simple cubic packing, making in efficient use of available space and hence minimizing the attractive forces.

Question 13.
What is meant by packing efficiency? How is ¡t measured?
Answer:
1. There is some free space between the spheres of a single layer and the spheres of successive layers.

2. The percentage of total volume occupied by these constituent spheres gives the packing efficiency of an arrangement. For eg., in simple cubic arrangement.

Question 14.
Calculate the packing efficiency in fcc unit cell?
Answer:
Total number of spheres belongs to a single fcc unit cell is 4. Volume of the sphere with radius r is = \(\frac { n }{ 2 }\) π \({ \left( \frac { \sqrt { 2 } a }{ 4 } \right) }^{ 3 }\)

Question 15.
How is radius ratio ¡s useful in determination of structure of an Ionic compound?
Answer:

1. The structure of an ionic compound depends upon the stoichiometry and the size of the ions.
2. Generally in ionic crystals, the bigger anions are present in the close packed arrangements the cations occupy the voids.
3. The ratio of radius of cation and anion plays an important role in determining the structure.
4. For Eg;

Question 16.
What Is meant by impurity defect? Explain with example?
Answer:

1. A method of introducing defects in ionic solids by adding impurity ions.
2. If the impurity ions are in different valence state from that of host, vaccancies are creited in the crystal lattice of the host.
3. For cg., addition of CdCl² to silver chloride yields solid solutions where the divalent cation Cd²⁺ occupies the position of Ag²⁺
4. This will disturb the electrical neutrality of the crystal. In order to maintain the same, proportional number of Ag ions leave the lattice. This produces a cation vaccancy in the lattice, such kind of crystal defects are called impurity defects.

Question 17.
A compound is formed by two elements M and N. The element N forms ccp and atoms of M occupy 1/3 rd of the tetrahedral voids. What is the formula of the compound?
Answer:
Suppose the atoms N in the ccp = n
∴ No. of tetrahedral voids = 2n
As 1/3 rd of the tetrahedral voids are occupied by atoms M, therefore,
No. of atoms M = \(\frac { 2n }{ 3 } \)
∴ Ratio of M : N = \(\frac { 2n }{ 3 } \) : n = 2 : 3
Hence, the formula is M₂N₃

Question 18.
How many lattice points are there in one unit cell of each of the following lattice?

1. Face – centred cubic
2. Face – centred tetragonal
3. Body – centered

Answer:

1. Lattice points in face-centred cubic lattice = 8 (at corners) + 6 (at the face centre) = 14
2. Face centred tetragonal = 8 (at corners) + 6 (at the face centre) = 14
3. Lattice points in body-centred cube = 8 (at corners) +1 (at the body centre) = 9

Question 19.
Explain:

1. The basis of similarities and differences between metallic and ionic crystals.
2. Ionic solids are hard and brittle.

Answer:
1. Similarities:

• Both ionic and metallic crystals have electrostatic forces of attractiàn.
• In ionic crystals these forces are between oppositely charged ions. In metals,these forces are among the valence electrons and posityely charged kernels.
• Both have high melting point.

Differences:

• Ionic bond is strong due to electrostatic forces of attraction whereas metallic bond may be weak or strong depending upon the number of valence electrons and the size of kernels.
• In ionic bond, ions are not free to move. Hence, they cannot conduct electricity in solid state. They can do so only in molten state or in aqueous solution. ¡n metals, electrons are free to move. Hence, they conduct electricity in solid state.

2. Ionic crystals are hard due to strong electrostatic forces between them. They are brittle because ionic bond is non – directional.

Question 20.
ZnO is colourless at room temperature, while yellow when hot, why?
Answer:
ZnO is colourless at room temperature. When it is heated, it becomes yellow in colour. On heating, it loses oxygen and thereby forming free Zn²⁺ ions. The excess Zn²⁺ ions move to interstitial sites and the electrons also occupy the interstitial positions.

Samacheer Kalvi 12th Chemistry Solid State 5 Mark Questions and Answers

Question 1.
What are general characteristics of solids?
Answer:

1. Solids have definite volume and shape.
2. Solids are rigid and incompressible.
3. Solids have strong cohesive forces.
4. Solids have short interatomic, ionic (or) molecular distances.
5. Their constituents (atoms, ions or molecules) have fixed positions and can only oscillate about their mean positions.
6. Unlike gases, in solids, the atoms, ions (or) molecules are held together by strong force of attraction.

Question 2.
Write a note about classification of solids with suitable examples.
Answer:

Question 3.
What are ionic solids? Give their characteristics.
Answer:

1. The structural units of an ionic crystals are cations and anions. They are bound together by strong Na electrostatic attractive forces.
2. To maximize the attractive force, cations are surrounded by as many anions as possible and vice versa.
3. Ionic crystals possess definite crystals structure.
4. Many solids are cubic close packed.

Characteristics

1. Ionic solids have high melting points.
2. These solids do not conduct electricity, because the ions are fixed in their lattice positions.
3. They do not conduct electricity in molten state (or) when dissolved in water, because the ions are free to move in the molten state or solution.
4. They are hard as only strong external force can change the relative positions of ions.
5. Example – The arrangement of Na and Cl ions in NaCI crystal.

Question 4.
What are molecular solids?Explain their classification with suitable examples.
Answer:
In molecular solids, the constituents are neutral molecules. They are held together by weak vander Waals forces. Generally molecular solids are soft and they do not conduct electricity. These molecular solids are further classified into three types.

1. Non polar molecular solids.
2. Polar molecular solids.
3. Hydrogen bonded molecular solids.

1. Non polar molecular solids

• In this type, molecules are held together by weak dispersion forces or London forces.
• They have low melting points and are usually in liquids or gaseous state at room temperature. Examples – Naphthalene, Anthracene etc.

2. Polar molecular solids

• In this type, molecules formed by polar covalent bonds.
• They are held together by strong dipole-dipole interactions.
• They have higher melting points than the non – polar molecular solids. Examples., solid CO₂, solid NH₃

3. Hydrogen bonded molecular solids

• The constituents are held together by hydrogen bonds.
• The constituents are held together by hydrogen bonds.
• They are soft solids under room temperature Examples: Solid ice, glucose, urea.

Question 5.
An element crystallizes in a fcc lattice with cell edge of 400 pm. The density of the element is 7 g/cm³. How many atoms one present in 280 g of the element?
Answer:
Volume of unit cell a³ (a = edge length)
= 400 pm
= (400 x 10^-12 m)³
= (400 x 100^-10 cm)³ = 64 x 10^-24 cm³

Since each f.c.c. unit cell contains 4 atoms therefore,
Total number =4 x 0.46 x 1024,
= 1.84 x 1024 atoms.

Common Errors

Common Errors

1. sc, bcc, fee structures may get confused if they ask in different order.
2. Calculation of atoms at each cube may get confused.
3. Sharing of atoms may get con¬fused.

Rectifications

1. In sc, only simple cube can be drawn, bcc structure is with one dot at centre, fee structure is with sc with six dots at each face.
   sc – only one atom, bcc – two atoms, fee – four atoms (we can remember as f and f).
2. Atom at comer is shard by 8 unit cells. Atom at centre is not shared. Atom at face is shared by 2 unit cells. Atom at edge is shared by 4 unit cells.

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Tamilnadu Samacheer Kalvi 12th Chemistry Solutions Chapter 11 Hydroxy Compounds and Ethers

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Samacheer Kalvi 12th Chemistry Chapter 11 Hydroxy Compounds and Ethers Textual Evaluation Solved

Samacheer Kalvi 12th Chemistry Hydroxy Compounds and Ethers Multiple Choice Questions

12th Chemistry Chapter 11 Book Back Answers Question 1.
An alcohol (x) gives blue colour in victormayer’s test and 3.7g of X when treated with metallic sodium liberates 560 mL of hydrogen at 273 K and 1 atm pressure what will be the possible structure of X?
(a) CH₃ CH (OH) CH₂CH₃
(b) CH₃ – CH(OH) – CH₃
(c) CH₃ – C (OH) (CH₃)₂
(d) CH₃ – CH₂ – CH (OH) – CH₂ – CH₃
Answer:
(a) CH₃ CH (OH) CH₂CH₃
Hint:
2R – OH + Na → 2RONa + 2H₂ ↑ 2 moles of alcohol gives 1 mole of H₂ which occupies
22.4L at 273K and 1 atm
number of moles of alcohol = \(\frac{2 \text { moles of } \mathrm{R}-\mathrm{OH}}{22.4 \mathrm{L} \text { of } \mathrm{H}_{2}}\) x 560 mL = 0.05 moles
number of moles = \(\frac{\text { mass }}{\text { molar mass }}\)
= molar mass = \(\frac{3.7}{0.05}\) = 74 g mol^-1
General formula for
R – OH C_n H_2n+1 – OH
n(12) + (2n+1) (1) + 16 +1 = 74
14n = 74 – 18
14n = 56
n = \(\frac { 56 }{ 4 }\) = 4
The 2° alcohol which contains 4 carbon is CH_n CH(OH)CH₂ CH₃

Hydroxy Compounds And Ethers Question 2.
Which of the following compounds on reaction with methyl magnesium bromide will give tertiary alcohol.
(a) benzaldehyde
(b) propanoic acid
(c) methyl propanoate
(d) acetaldehyde
Answer:
(c) methyl propanoate
Hint:

12th Chemistry Evaluate Yourself Answers Question 3.

This ‘X’ is …………..

Answer:

Hint:
hydro boration – Anti markownikoff product
i.e CH₃ – CH₂ – CH – CH₂ – CH₂ – OH

Hydroxy Compounds And Ethers Pdf Question 4.
In the reaction sequence, Ethane

Ethan – 1, 2 – diol. A and X respectively are ………….
(a) Chioroethane and NaOH
(b) ethanol and H₂SO₄
(c) 2 – chloroethan – 1 – ol and NaHCO₃
(d) ethanol and H₂O
Answer:
(c) 2 – chloroethan – 1 – ol and NaHCO₃
Hint:

Hydroxy Compounds And Ethers Class 12 Question 5.
Which one of the following is the strongest acid ………..
(a) 2 – nitrophenol
(b) 4 – chlorophenol
(c) 4 – nitrophenol
(d) 3 – nitrophenol
Answer:
(c) 4 – nitrophenol

Hydroxy Compounds And Ethers Important Questions Question 6.

on treatment with Con. H₂SO₄, predominately gives ……………..

Answer:

Hint:

12th Chemistry Evaluate Yourself Answers Samacheer Question 7.
Carbolic acid is …………..
(a) Phenol
(b) Picric acid
(c) benzoic acid
(d) phenylacetic acid
Answer:
(a) Phenol

12th Chemistry Book Inside Evaluate Yourself Answers Question 8.
Which one of the following will react with phenol to give salicyladehyde after hydrolysis …………..
(a) Dichioro methane
(b) trichioroethane
(c) trichloro methane
(d) CO₂
Answer:
(c) trichloro methane (Riemer Tiemann reaction)
Hint:

12th Chemistry Evaluate Yourself Answers Pdf Question 9.

(a) (CH₃)₃ CCH = CH₂
(b) (CH₃)₂ C = C (CH₃)₂
(c) CH₂ = C(CH₃)CH₂ – CH₂ – CH₃
(d) CH₂ = C (CH₃) – CH₂ – CH₂ – CH₃
Answer:
(b) (CH₃)₂ C = C (CH₃)₂
Hint:

12th Chemistry Evaluate Yourself Answers Pdf Download Question 10.
The correct IUPAC name of the compound,

(a) 4 – chloro – 2, 3 – dimethyl pentan – 1 – ol
(b) 2, 3 – dimethyl – 4 – chloropentan – 1 – ol
(c) 2, 3, 4 – trimethyl – 4 – chiorobutan – 1 – ol
(d) 4 – chioro – 2, 3, 4 – trimethyl pentan – 1 – ol
Answer:
(a) 4 – chloro – 2, 3 – dimethyl pentan – 1 – ol

12 Chemistry Evaluate Yourself Answers Question 11.
Assertion: Phenol is more acidic than ethanol
Reason: Phenoxide ion is resonance stabilized
(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:
if both assertion and reason are true and reason is the correct explanation of assertion.

12th Std Chemistry Evaluate Yourself Answers Question 12.
In the reaction Ethanol
is ………………
(a) ethane
(b) ethoxyethane
(c) ethylbisuiphite
(d) ethanol
Answer:
(d) ethanol
Hint:

12th Chemistry Evaluate Yourself Answers Chapter 11 Question 13.
The reaction

can be classified as
(a) dehydration
(b) Williams on alcoholsynthesis
(c) Williamson ether synthesis
(d) dehydrogenation of alcohol
Answer:
(c) Williamson ether synthesis
Hint: Cyclic alcohol → sodium cyclic alkoxide → williamson ether synthesis

Samacheer Kalvi Guru 12th Chemistry Question 14.
Isoprophylbcnzene on air oxidation in the presence of dilute acid gives …………
(a) C₆H₅COOH
(b) C₆H₅COCH₃
(c) C₆H₅COC₆H₅
(d) C₆H₅ – OH
Answer:
(a) C₆H₅ – OH (phenol)

11th Chemistry Evaluate Yourself Answers Chapter 11 Question 15.
Assertion: Phenol is more reactive than benzene towards electrophilic substitution reaction
Reason: In the case of phenol. the intermediate arenium ion is more stabilized by resonance.
(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.

Samacheer Kalvi 12th Chemistry Solutions Question 16.
HO CH₂ CH₂ – OH on heating with periodic acid gives ………..
(a) methanoic acid
(b) Glyoxal
(c) methanol
(d) CO₂
Answer:
(c) methanol

Question 17.
Which of the following compound can be used as artireeze in automobile radiators?
(a) methanol
(b) ethanol
(c) Neopentyl alcohol
(d) ethan -1, 2-diol
Answer:
(d) ethan -1, 2-diol

Question 18.

is an example of …………..
(a) Wurtz reaction
(b) cyclic reaction
(c) Williamson reaction
(d) Kolbe reactions
Answer:
(c) Kolbe reactions

Question 19.
One mole of an organic compound (A) with the formula C₃H₈O reacts completely with two moles of HI to form X and Y. When Y is boiled with aqueous alkali it forms Z. Z answers the iodoform test. The compound (A) is ……………
(a) propan – 2 – ol
(b) propan- 1- ol
(c) ethoxy ethane
(d) methoxy ehane
Answer:
(d) methoxy ehane
Hint:

Question 20.
Among the following ethers which one will produce methyl alcohol on treatment with hot HI?

Answer:

Hint:

Question 21.
Williamson synthesis of preparing dimethyl ether is a / an /
(a) SN¹ reactions
(b) SN² reaction
(c) electrophilic addition
(d) electrophilic substitution
Answer:
(b) SN² reaction

Question 22.
On reacting with neutral ferric chloride, phenol gives
(a) red colour
(b) violet colour
(c) dark green colour
(d) no colouration
Answer:
(b) violet colour

II. Answer the following questions

Question 1.
IdentIfy the product (s) is / are formed when 1 – methoxy propane is heated with excess HI. Name the mechanism involved in the reaction
Answer:
1-methoxy propane is heated with excess HI, yields two products named as Methyl iodide and 1- iodo propane.
Step 1:

Step 2.

Step 3:

Step 4:

Overall reaction:

This reaction ivvolves nucleophilic substitution reaction mechanism. (SN¹)

Question 2.
Draw the major product formed when 1 – ethoxyprop – 1 – ene is heated with one equivalent of HI
Answer:

This reaction follows SN¹ mechanism because in this reaction the more stable carbocation is formed that is double bonded carbocation. Therefore, the given molecule reacts with HI to form ethanol and 1- iodo prop – 1 – ene.

Question 3.
Suggest a suitable reagent to prepare secondary alcohol with identical group using Grignard reagent.
Answer:
Acetaldehyde reacts with Grignard reagent to give addition product, which on further undergoes acid hydrolysis to yield secondary alcohol, that is isopropyl alcohol.

Question 4.
What is the major product obtained when two moles of ethyl magnesium bromide is treated with methyl benzoate followed by acid hydrolysis
Answer:

Question 5.
Predict the major product, when 2-methyl but – 2 – ene is converted into an alcohol in each of the following methods.

1. Acid catalysed hydration
2. Hydroboration
3. Hydroylation using bayers reagent

Answer:
1. Acid catalysed hydration:

2. Hydroboration.

3. Hydroxylation using bayers reagent:

Question 6.
Arrange the following in the increasing order of their boiling point and give a reason for your ordering

1. Butan – 2 – ol, Butan – 1 – SI, 2 – methylpropan – 2 – ol
2. Propan – 1 – ol, propan – 1, 2, 3 – triol, propan – 1, 3 – diol, propan – 2 – ol

Answer:
1. Boiling points increases regularly as the molecular mass increases due to a corresponding increase in their Van der waal’s force of attraction. Among isomeric alcohols 2° – alcohols have lower boiling points than 1° – alcohols due to a corresponding decreases in the extent

of H-bonding because of steric hindrance. Thus the boiling point of Butan – 2 – ol is lower than that of Butan – 1 – ol. Overall increasing order of boiling points is, 2 – methylpropan – 2 – ol < Butan – 2 – ol < Butan – 1 – ol

2. 2°-alcohols have lower boiling points than 1° – alcohols due to a corresponding decrease in the extent of H – bonding because of steric hindrance. Therefore Propan – 1 – ol has higher boiling point than Propan – 2 – ol. Hydrogen group increases, boiling point also increases. Overall increasing order of boiling points is, propan – 2 – ol < Propan – 1 – ol < propan – 1, 3 – diol < propan -1, 2, 3 – triol

Question 7.
Can we use nucelophiles such as NH₃,CH₃O for the Nucleophilic substitution of alcohols
Answer:
1. Increasing order of nucelophilicity,
NH₃ < – OH^⊕ < CH₃O^⊖-

2. Higher electron density will increase the nucelophilicity.

3. Negatively charged species are almost always more nucelophiles than neutral species.

4. RO^⊖ has an alkyl group attached, allowing a greater amount of polarizability. This means oxygen’s lone pairs will be more readily available to reach in RO^⊖ than in OH^⊖. Hence CH₃O – is the better nucelophile for the nucleophilic substitution of alcohols. NH₃ cannot act as nucelophile for the nucleophilic substitution of alcohols.

Question 8.
Is it possible to oxidise t – butyl alcohol using acidified dichromate to form a carbonyic compound.
Answer:
3° – alcohols do not undergo oxidation reaction under normal condition, but at elevated temperature, under strong oxidising agent cleavage of C – C bond takes place to give a mixture of carboxylic acid.

Yes, it is possible. t – butyl alcohol is readily oxidsing in acidic solution (K₂Cr₂O₇ / H₂SO₄) to a mixture of a ketone and an acid each containing lesser number of carbon atoms than the original alcohol. The oxidation presumably occur via alkenes formed through dehydration of alcohols under acidic conditions.

Question 9.
What happens when 1 – phenyl ethanol is treated with acidified KMnO₄.
Answer:
1 – phenyl ethanol reacts with acidified KMnO₄ to give Acetophenone.

Question 10.
Write the mechanism of acid catalysed dehydration of ethanol to give ethene.
Mechanism of acid catlaysed dehydration of ethanol:
Step1:
Protonation of ethanol.

Step 2:
Elimination of water molecule.

Question 11.
How is phenol prepared form

1. chloro benzene
2. isopropyl benzene

Answer:
1. From Chioro benzene:
According to Dow’s process, when Chiorobenzene is hydrolysed with 6 – 8% NaOHat 300 bar and 633K in a closed vessel, sodium phcnoxidc is formed which on treatment with dilute HCl gives phenol.

2. For isopropyl benzene:
On passing air to a mixture of cumene (isoprophy benzene) and 5% aqueous sodium carbonate solution, cumene hydro peroxide is formed by oxidation. It is treated with dilute acid to get phenol and acetone.

Question 12.
Explain Kolbe’s reaction
Answer:
Kolbe’s (or) Kolbe’s Schmitt reaction:
In this reaction, phenol is first converted into sodium phenoxide which is more reactive than phenol towards electrophilic substitution reaction with CO₂. Treatment of sodium phenoxide with CO₂ at 400K, 4 -7 bar pressure followed by acid hydrolysis gives salicylic acid.
Answer:

Question 13.
Writes the chemical equation for Williamson synthesis of 2 – ethoxy – 2 – methyl pentane starting from ethanol and 2 – methyl pentan – 2 – ol
Answer:
Step 1:

Step 2:

Step 3:

Williamsons synthesis occurs by SN² – mechanism and primary alkyl halides are more reactive in SN² reactions. Therefore ethanol is converted into ethyl bromide.

Question 14.
Write the structure of the aldehyde, carboxylic acid and ester that yield 4 – methylpent – 2 – en – 1 – ol.
Answer:
1. Aldehyde yield 4 – methylpent – 2 – 3n – ol is

2. Acid yield 4 – methylpent – 2 – en – 1 – ol is

3. Ester yield 4 – methylpent – 2 0 en – l – ol is

The above shown compounds undergo reduction reaction to yield 4 – methylpent – 2 – en – l – ol.

Question 15.
What is meta merism? Give the structure and IUPAC name of metamers of 2 – methoxy propane
Answer:
Metamerism:
It is a special type of isomerism in which molecules with same formula, same functional group, but different only in the nature of the alkyl group attached to oxygen.

Ethoxy ethane and 1-methoxy propane are metamers of 2-methoxy propane.

Question 16.
How are the following conversions effected

1. benzylchlorjde to benzvlalcohol
2. benzvl alcohol to benzoic acid

Answer:
1. Conversion of benzyl chloride into benzyl alcohol:

2. Conversion of benzyl alcohol into benzoic acid:

Question 17.
Complete the following reactions

Answer:

Question 18.
O.44g of a monohydric alcohol when added to methyl magnesium iodide in ether liberates at STP 112 cm³ of methane with PCC the same alcohol form a carbonyl compound that answers silver mirror test. Identify the compound.
Answer:
0.44g of a monohydric alcohol liberates 112 cm³ of methane.

Mass of monohydric alcohol which gives 22400 cm3 of methane = \(\frac{22400 \times 0.44}{112}\) = 88
C₅H₁₂O molecular fórmula has mass number 88 and it shows eight possible isomers. But neopentyl alcohol reacts with PCC to form neopentyl aldehyde, which shows positive silver mirror test. Therefore, compound is. neopentyl alcohol (or) 2, 2 – dimethyl propan – l – ol.

Question 19.
Complete the following reactions

Answer:

Question 20.
Phenol is distilled with Zn dust gives (A) followed by friedel – crafts alkylation with propyl chloride to give a compound B, B on oxidation gives (C). Identify A,B and C.
Answer:

Question 21.

Identify A, B, C, D and write the complete equation.
Answer:

Question 22.
What will be the product for the following reaction

Answer:

Question 23.
How will you convert acetylen in to n – butyl alcohol.
Answer:

Question 24.
Predict the product A, B, X and Y in the following sequence of reaction

Answer:

Question 25.
3,3 – dimethylbutan – 2 – ol on treatment with conc. H₂SO₄ to give tetramethyl ethylene as a major product. Suggest a suitable mechanisms
Answer:

According to Saytzeff’s rule the dehydration of 3,3 – dimethylbutan – 2 – ol gives a mixture of alkenes. But the secondary carbocation formed in this reaction undergoes rearrangement to form a more stable tertiary

carbocation which further, undergoes to 13 – elimination leads more stable product, that is 2,3 – dimethyl but – 2 – ene (more yield). According to Saytzeff’s nile, 2, 3 – dimethyl pent- 2 – ene is the major product.

Samacheer Kalvi 12th Chemistry Hydroxy Compounds and Ethers Evaluate yourself

Question 1.
Classify the following alcohols as 1⁰, 2⁰, and 3⁰ and give their IUPAC Names.

Answer:

Question 2.
Write all the possible isomers of an alacohol having the molecular formula C₁₅H₁₂O and their IUPAC names.
Answer:
Eight isomers are possibe for C₁₅H₁₂O. They are,

Question 3.
Suggest a suitable carbonyl compound for the preparation of pent – 2 – en – 1 ol using LiAlH₄.
Answer:

Question 4.
2 – methylpropan – 2 – ene
Answer:

Question 5.
How will you prepare the following using Grignard reagent.

1. t – butyl alcohol
2. allyl alcohol

Answer:

Question 6.
Identify the products in the following reactions. Write their IUPAC names and mention the mechanism involved in the reactions.

Answer:
1.
This reaction involves E₁ – mechanism.

2.
This reaction ivolves SN² – mechanims.

3. Step 1:

Step 2:

This reaction involves SN² Mechanims.

Question 7.
What is the major product obtained when 2,3 – dimethyl pentan – 3 – ol is heated in the presence of H₂SO₄
Answer:

According to Saytzeff’s rule, 2, 3 – dimethyl pent – 2 – ene is the major product.

Question 8.
Which of the following set of reactants will give 1 – methoxy – 4 – nitrobenzene.

Answer:
Step 1:

step 2:

Chemically both sets equally possible. In Set – 1, the Br-atom is activated by electron withdrawing effect of – NO₂ group. Therefore nucleophilic attack by CH₃ONa followed by elimination of NaBr gives the desired ether.

Step 1:

Step 2:

In set – 2, nucleophilic attack by 4 – nitrosodium phenoxide ion on methyl bromide gives the desired ether.

Since alkyl halides (CH₃Br) are more reactive than aryl halides in nucleophilic substitution reactions, therefore set – 2 reactants are preferred.

Question 9.
What happens when m – cresol is treated with acidic solution of sodium dichromate?
Answer:

When m – cresol is treated with acidic solution of sodium dichromate it gives 4 – hydroxy beazoic acid.

Question 10.
When phenol is treated with propan – 2 – ol in the presence of HF, Friedel – Craft reaction takes place. Identify the products.
Answer:

Question 11.
Given the IUPAC name for the following ethers and classify them as simple or mixed.
Answer:

Question 12.
1. Which of the following reaction will give 1 – methoxy – 4 – nitrobenzene.

1. 4 – nitro – 1 – bromobenzene + sodium methoxide.
2. 4 – nitrosodium phenoxide + bromomethane

Answer:
1. Set – 1:

2. set – 2:

Chemically both sets equally possible. In Set – 1, the Br – atom is activated by electron withdrawing effect of – NO₂ group. Therefore nucleophilic attack by CH₃ONa followed by elimination of NaBr gives the desired ether.
Step 1:

Step 2:

In set – 2, nucleophilic attack by 4 – nitrosodium phenoxide ion on methyl bromide gives the desired ether.

Since alkyl halides (CH₃Br) are more reactive than aryl halides in nucleophilic substitution reactions, therefore set – 2 reactants are preferred.

Question 13.
Arrange the following compounds in the increasing order of their acid strength. propan – 1 – ol, 2, 4, 6 – trinitroptienol, 3 – nitrophenol, 3,5 – dinitrophenol, phenol, 4 – methyiphenol.
Answer:
Phenols are stronger acids than alcohols because the phenoxide ion left after the removal of proton is stabilized by resonance while the alkoxide ion left after the removal of a proton from alcohol is not stabilized. Thus propan – 1 – ol is much weaker acid than any phenol.

Thus propan- 1 – ol is a much weaker acid than any phenol. We know that electron donating groups decrease the acidic character and stronger is the electron donating group, weaker is the phenol.

Compare to propan – 1 – ol, 4 – methyl phenol is stronger acidic character. But comparing phenol and 4-methyl phenol, phenol is stronger acidic. Since electron withdrawing groups increase the acidic character of phenols and the effect is more pronounced at the para position than at the meta position.

Therefore 4 – nitro phenol is a stronger acid than 3 – nitro phenol. Further as the number of electron withdrawing groups increases the acidic strength further increases. Therefore 2, 4, 6 – trinitro phenol is a stronger acid than 3, 5 – dintiro phenol. It may be noted here that although the two nitro groups in 3, 5 – dinitro phenol are at m – position with respect to OH group,

their combined effect is however greater than one nitro group at p – position. Therefore 3, 5 – dinitro phenol is a stronger acid than 4-nitro phenol. Thus, the overall increasing order of acid strength is. Propan – 1 – 01 < 4 – methyl phenol < phenol < 3 – nitrophenol < 3, 5 – dinitro phenol < 2, 4, 6 – trinitro phenol.

Question 14.
1 mole of HI is allowed to react with t – butyl methylether. Identify the product and write down the mechanism of the reaction.
Answer:
Step 1:

Step 2

Step 3:

Overall reaction:

Samacheer Kalvi 12th Chemistry Hydroxy Compounds and Ethers Additional Questions

Samacheer Kalvi 12th Chemistry Hydroxy Compounds and Ethers 1 Mark Questions and Answers

I. Choose the best answer.

Question 1.
Which one of the following is a trihydric alcohol?
(a) Glycol
(b) Ethanol
(c) Glycerol
(d) Sorbitol
Answer:
(c) Glycerol

Question 2.
Identify the monohydric unsaturated alcohol.

Answer:

Question 3.
Which one of the following is named as sorbital?

Answer:

Question 4.
Which one of the following is a primary alcohol?

Answer:

Question 5.
Which of the following is a dihydric alcohol?
(a) Ethenol
(b) Ethanol ]
(c) Ethane – 1, 2 – diol
(d) Propan – 2 – ol
Answer:
(c) Ethane – 1, 2 – diol

Question 6.
Which one of the following is an example of secondary (2°) alcohol?
(a) Propan – 2 – ol
(b) Phenyl methanol
(c) Ethenol
(d) 2 – methyl – propan – 2 – ol
Answer:
(a) Propan – 2 – ol

Question 7.
Which one of the following is a tertiary alcohol?

Answer:

Question 8.
Which of the following is a primary alcohol?

Answer:

Question 9.
Which one of the following find application in proper functioning of our eyes?
(a) Cholesterol
(b) Retinol
(c) Phenol
(d) Ethanol
Answer:
(b) Retinol

Question 10.
Which is the storage of vitamin – A?
(a) Retinol
(b) Benzyl alcohol
(c) Phenol
(d) Ascorbic acid
Answer:
(a) Retinol

Question 11.
The important component in our cell membrane is ………….
(a) Retinol
(b) Phenol
(c) Cholesterol
(d) Methanol
Answer:
(c) Cholesterol

Question 12.
Which acts as an additive to petrol?
(a) Glycerol
(b) Ethanol
(c) Phenol
(d) Methanol
Answer:
(b) Ethanol

Question 13.
Which one of the following vitamin is stored in Retinol?
(a) Vitamin – B₁₂
(b) Vitamin – A
(c) Vitamin – C
(a) Vitamin – D
Answer:
(b) Vitamin – A

Question 14.
Which alcohol is used as skin cleanser for injection?
(a) Methanol
(b) Ethanol
(c) 1 -propanol
(d) 2-propanol
Answer:
(d) 2-propanol

Question 15.
Which one of the following is used as an industrial solvent?
(a) Methanol
(b) Benzyl alcohol
(c) Phenol
(d) Cholesterol
Answer:
(a) Methanol

Question 16.
2 – methyl but – 3 – en – 2 – ol belongs to which type of alcohol?
(a) 3° alcohol
(b) 2° alcohol
(c) 1° alcohol
(d) Aromatic alcohol
Answer:
(a) 3° alcohol

Question 17.
The IUPAC name of

(a) 1 – methyl – 2 – propanol
(b) 2 – methyl – p ropan – 2 – ol
(c) Tertibutyl alcohol
(d) 2 – propanol
Answer:
(b) 2 – methyl – p ropan – 2 – ol

Question 18.
The TUPAC name of CH₂ = CH – CH₂OH is …………
(a) Allyl alcohol
(b) Propenc – 2 – ol
(c) Prop – 2 – en – 1 – oI
(d) Isopropyl alcohol
Answer:
(c) Prop – 2 – en – 1 – oI

Question 19.
In methanol, – OH group attached to carbon is ………..
(a) sp hybridised atom
(b) sp³ hybridised atom
(c) sp² hybridised atom
(d) dsp² hybridised atom
Answer:
(c) sp² hybridised atom

Question 20.
Which one of the following is C – O – H bond angle in methanol?
(a) 109.5°
(b) 104°
(c) 90°
(d) 108.9°
Answer:
(d) 108.9°

Question 21.
Primaiy alkyl halides undergoes substitution by ……….
(a) SN¹ reaction
(b) SN_i reaction
(c) SN² reaction
(d) SN reaction
Answer:
(c) SN² reaction

Question 22.
What is the product formed when propene is hydrolysed in the presence of mineral acid?
(a) Propan – 1 – ol
(b) Propan – 2 – ol
(c) Iso butyl alcohol
(d) 2 – mcthyl – propan – 2 – ol
Answer:
(b) Propan – 2 – ol

Question 23.
The product formed when phenyl magnesium bromide treated with methanal and hydrolysed is ………..
(a) Phenyl methanal
(b) Phenol
(c) Phenyl methanol
(d) Benzyl benzoate
Answer:
(c) Phenyl methanol

Question 24.
To get Butan – 2 – ol, Ethyl magnesium bromide is treated with followed by hydrolysis.
(a) HCHO
(b) CH₃COCH₃
(c) CO₂
(d) CH₃CHO
Answer:
(d) CH₃CHO

Question 25.
Which one of the following is formed when Butyl magnesium bromide is treated with propanone followed by hydrolysis?
(a) Tertiary butyl alcohol
(b) Isopropyl alcohol
(c) 2 – methyl hexan – 2 – ol
(d) Propan – 1 -ol
Answer:
(c) 2 – methyl hexan – 2 – ol

Question 26.
Which one of the tbllowing is used to get propan – 2 – ol by the reaction with CH₃MgBr?
(a) Ethanol
(b) Ethanal
(c) Ethyl inethanoate
(d) Propanone
Answer:
(c) Ethyl inethanoate

Question 27.
Crotanaldehyde on reaction with LiAlH₄ and water produces
(a) Ethanol
(b) Propan – 2 – ol
(c) Methanol
(d) But – 2 – en – 1 – ol
Answer:
(d) But – 2 – en – 1 – ol

Question 28.
Which one of the following is used as a catalyst in the conversion of Bcnzoic acid to Benzyl alcohol?
(a) Ni
(b) LiAIH₄ / H₂O
(c) Sn / HCI
(d) Zn / NaOH
Answer:
(b) LiAIH₄ / H₂O

Question 29.
What is the product formed when acetone is treated with LiA1H4 and 1120?
(a) Isobutyl alcohol
(b) n – butyl alcohol
(c) Propan – 2 – ol
(d) Propan – 1 – ol
Answer:
(c) Propan – 2 – ol

Question 30.
Which one of the following is formed when ethene reacts with Baeyer’s reagent?
(a) Ethane
(b) Ethylene glycol
(c) Propane – 1, 2 – diol
(d) Glycerol
Answer:
(b) Ethylene glycol

Question 31.
Which one of the following is named as Baeyer’s reagent?
(a) acidified K₂Cr₂O₇
(b) acidified KMnO₄
(c) Cold dilute alkaline KMnO₄
(d) LiAlH₄
Answer:
(c) Cold dilute alkaline KMnO₄

Question 32.
The alkaline hydrolysis of fats to give glycerol is known as …………
(a) Esterification
(b) Hydroboration
(c) Hydration
(d) Saponification
Answer:
(d) Saponification

Question 33.
Which one of the following alcohol reacts immediately with Lucas reagent?
(a) Primaiy alcohol
(b) Tertiary alcohol
(c) Phenol
(d) Secondary alcohol
Answer:
(b) Tertiary alcohol

Question 34.
Which one of the following is called Lucas reagent?
(a) Conc. HCl + Anhydrous ZnCl₂
(b) Conc. HCl + Anhydrous A1CI₃
(c) LiAIH₄ + H₂O
(d) Cold dilute alkaline KMnO₄
Answer:
(a) Conc. HCl + Anhydrous ZnCl₂

Question 35.
Which alcohol gives red colour in Victor Meyer’s test?
(a) 2° alcohol
(b) 3° alcohol
(c) Phenol
(d) 1° alcohol
Answer:
(d) 1° alcohol

Question 36.
Which colour is given by secondary alcohol in Victor Meyer’s test?
(a) Red
(b) Green
(c) Blue
(d) Yellow
Answer:
(c) Blue

Question 37.
Which mechanism is followed in the reaction of 2 – methyl – 2 – propanol with HBr?
(a) E₁ mechanism
(b) E₂ mechanism
(c) SN² mechanism
(d) SN¹ mechanism
Answer:
(d) SN¹ mechanism

Question 38.
Which mechanism is followed in the conversion of ethanol to bromoethane by HBr?
(a) SN¹ mechanism
(b) SN² mechanism
(c) E₁ mechanism
(d) E₂ mechanism
Answer:
(c) E₁ mechanism

Question 39.
Which one of the following is used as a catalyst in the reaction of methanol with thionyl chloride?
(a) Pyridine
(b) pyrrole
(c) THF
(d) Nickel
Answer:
(a) Pyridine

Question 40.
The mechanism of the reaction of ethanol with PCl₃ is ……………..
(a) SN¹
(b) SN²
(c) E₂
(d) E₁
Answer:
(b) SN²

Question 41.
Which one of the following reagent is used in the conversion of Ethanol to ethene?
(a) Zn + Hg / H₂O
(b) LiAlH₄
(c) acidified K₂Cr₂O₇
(d) Conc. H₂SO₄
Answer:
(d) Conc. H₂SO₄

Question 42.
Primary alcohol undergo dehydration by ………
(a) E₁ mechanism
(b) E₂ mechanism
(c) SN¹ mechanism
(d) SN² mechanism
Answer:
(b) E₂ mechanism

Question 43.
Tertiary alcohols undergo dehydration by ……….
(a) SN¹ mechanism
(b) E₂ mechanism
(c) E₁ mechanism
(d) SN² mechanism
Answer:
(c) E₁ mechanism

Question 44.
Which one of the following is the correct order of relative reactivities of alcohols in the dehydration reaction?
(a) 1° < 2° < 3°
(b) 2° < 1° < 3°
(c) 3° < 2° < 1°
(d) 3° < 1° < 2°
Answer:
(a) 1° < 2° < 3°

Question 45.
Which of the following is the product formed when 3,3 – dimethyl – 2 – butanol reacts with conc.H₂SO₄?
(a) 2, 3 – dirnethyl but – 1 – ene
(b) 2,3 – dimethyl but – 2 – ene
(c) 3, 3 – dimethyl but – 1 – ene
(d) all the above
Answer:
(d) all the above

Question 46.
The oxidising agent used to prepare aldehyde (or) ketone from alcohol, the reagent used is …………..
(a) acidified Na₂Cr₂O₇
(b) alkaline KMnO₄
(c) Pyridinium chlorochromate
(d) conc. H₂SO₄
Answer:
(c) Pyridinium chlorochromate

Question 47.
The product formed when propan – 2 – ol is treated with dimethyl sulfoxide (DMSO) and oxalyl chloride followed by the addition of Et₃N is ……….
(a) Oxalyl chloride
(b) Propanal
(c) Ethanoic aicd
(d) Propanone
Answer:
(d) Propanone

Question 48.
Which reaction is used to convert alcohol to ketone / aldehyde in the presence of DMSO?
(a) Lucas test
(b) Swern oxidation
(c) Biological oxidation
(d) Kolbe’s reaction
Answer:
(b) Swern oxidation

Question 49.
Which product is formed when propan- 1 – ol is oxidised by pyridinium chlorochromate (PCC)?
(a) Propanal
(b) Propanone
(c) Propane
(d) Propene
Answer:
(a) Propanal

Question 50.
Which one of the enzyme is produced in liver to detoxify the alcohol?
(a) Diastase
(b) Zymase
(c) Invertase
(d) Dehydrogenase alcohol
Answer:
(d) Dehydrogenase alcohol

Question 51.
What isADH and NAD?
(a) Alcohol dehydrogenase and nicotinamide adenine dinucleotide
(b) Acid dehydration and Nitrogen addition
(c) Alcohol dehydration and Nicotine addition
(d) Adeninc hydrogenase and Nicotinamide adenine dinucleotide
Answer:
(a) Alcohol dehydrogenase and nicotinamide adenine dinucleotide

Question 52.
What is the main reaction take place when 2 – methyl propan – 2 – ol reacts with Cu at 573 K?
(a) Dehydrogenation
(b) Oxidation
(c) Dehydration
(d) Hydrogenation
Answer:
(c) Dehydration

Question 53.
Name the product formed when tertiary butyl alcohol is treated with Cu at 573 K?
(a) 2 – methyl prop – 1 – ene
(b) 2 – methyl prop – 2 – ene
(c) propene
(d) 1 – butene
Answer:
(a) 2 – methyl prop – 1 – ene

Question 54.
Which one of the following product is formed when propan – 2 – ol is treated with Cu at 573 K?
(a) Propanal
(b) Propanone
(c) Propan – 1 – ol
(d) Propane
Answer:
(b) Propanone

Question 55.
What is the name of the reaction between ethanol and ethanoic acid?
(a) Esterification
(b) Saponification
(c) Ethenfication
(d) Hydroxylation
Answer:
(a) Esterification

Question 56.
Which one of the following is formed when ethan – 1, 2 – diol is treated with PI₃?
(a) Ethane
(b) Ethyne
(c) Ethene
(d) Ethanol
Answer:
(c) Ethene

Question 57.
Which reagent is used to convert ethylene glycol to ethylene?
(a) HI
(b) I₂
(c) PI₃
(d) Conc. H₂ SO₄
Answer:
(c) PI₃

Question 58.
What is the product formed when ethylene glycol is heated at 773 K?
(a) Ethanal
(b) Ethene
(c) Ethane
(d) Oxirane
Answer:
(d) Oxirane

Question 59.
Which reagent is used to convert ethan – 1, 2 – diol into Ethanal?
(a) Anhydrous ZnCI₂
(b) Dilute. H₂SO₄
(c) Either (a) or (b)
(d) Conc. H₂SO₄
Answer:
(c) Either (a) or (b)

Question 60.
Name the product formed when ethan- 1, 2-diol is treated with anhydrous ZnCl₂.
(a) Ethanol
(b) Ethene
(c) Ethane
(d) Ethanal
Answer:
(d) Ethanal

Question 61.
Which one of the following is formed when ethane – 1, 2 – diol is treated with Conc. H₂ SO₄?
(a) 1, 4 – dioxane
(b) Ethanal
(c) Ethanoic acid
(d) Ethene
Answer:
(a) 1, 4 – dioxane

Question 62.
Which one of the following is formed when ethylene glycol is treated with periodic acid?
(a) Methanal
(b) Methanol
(c) Ethanol
(d) Ethanal
Answer:
(a) Methanal

Question 63.
Identify the product formed when glycerol is treated with nitric acid and conc. H₂SO₄?
(a) Nitroglycerine
(b) Glyceryl triacetate
(c) Prop – 2 – enal
(d) Glyceric acid
Answer:
(a) Nitroglycerine

Question 64.
What will be the product formed when propan – 1, 2, 3 – triol is treated with KHSO₄?
(a) Nitroglycerine
(b) TNG
(c) Prop – 2 – enal
(d) Allyl alcohol
Answer:
(a) Nitroglycerine

Question 65.
Oxidation of glycerol with dil.HNO₃ gives ………
(a) Meso oxalic acid
(b) Glyceric acid and tartronic acid
(c) Glycerose
(d) Glyceraldehyde and dihydroxy acetone
Answer:
(b) Glyceric acid and tartronic acid

Question 66.
Oxidation of glycerol with Fenton reagent gives ………..
(a) Glyceraldehyde + Dihydroxy acetone
(b) Glyceric acid + Tartronic acid
(c) Meso oxalic acid
(d) Oxalic acid
Answer:
(a) Glyceraldehyde + Dihydroxy acetone

Question 67.
Which one of the following product is formed when glycerol is oxidised with acidified KMnO₄?
(a) Meso oxalic acid
(b) Oxalic acid
(c) Formic acid
(d) Glyceric acid
Answer:
(b) Oxalic acid

Question 68.
Which one of the following is used as a solvent for paints, varnishes and gum?
(a) Ethanol
(b) Methanol
(c) Methanal
(d) Ethanal
Answer:
(b) Methanol

Question 69.
Which one of the following is used as fuel for aeroplane?
(a) Methanol + Ethanol
(b) Ethanol + Petrol
(c) Ethanol + Propanol
(d) Butanol + Methanol
Answer:
(b) Ethanol + Petrol

Question 70.
Which one of the following is used as beverage as well as preservative for biological specimens?
(a) Ethanol
(b) Methanol
(c) Phenol
(d) Benzyl alcohol
Answer:
(a) Ethanol

Question 71.
Which one of the following is used as an anti-freezer in automobile radiator?
(a) Glycerol
(b) Phenol
(c) Benzyl alcohol
(d) Ethylene glycol
Answer:
(d) Ethylene glycol

Question 72.
Which one of the following is used as a sweetening agent in confectionery and beverages?
(a) Glycerol
(b) Phenol
(c) Benzyl alcohol
(d) Ethylene glycol
Answer:
(a) Glycerol

Question 73.
Which one of the following is used in the manufacture of cosmetics and transparent soaps?
(a) Methanol
(b) Ethanol
(c) Glycerol
(d) Phenol
Answer:
(c) Glycerol

Question 74.
Which one of the following is used in the manufacture of explosive dynamite and cordite by mixing it with clay?
(a) Glycol
(b) Glycerol
(c) Ethanol
(d) Benzaldehyde
Answer:
(b) Glycerol

Question 75.
Which alcohols is used in making printing inks and stamp pad ink?
(a) Glycol
(b) Ethanol
(c) Glycerol
(d) Phenol
Answer:
(c) Glycerol

Question 76.
Except which alcohol, other alcohols are weaker acid than water?
(a) Ethanol
(b) Phenol
(c) Methanol
(d) Propanol
Answer:
(c) Methanol

Question 77.
Which one of the following is the correct decreasing order of acidity in alcohol?
(a) 1° alcohol > 2° alcohol > 3° alcohol
(b) 3° alcohol > 2° alcohol> 1° alcohol
(c) 2° alcohol> 1° alcohol > 3° alcohol
(d) 3° alcohol > 1° alcohol > 2° alcohol
Answer:
(a) 1° alcohol > 2° alcohol > 3° alcohol

Question 78.
Which one of the following is more acidic?
(a) Benzyl alcohol
(b) Phenol
(c) Ethanol
(d) Methanol
Answer:
(b) Phenol

Question 79.
The JUPAC name of Phioroglucinol is ………….
(a) 4 – methyl phenol
(b) 1, 4 – dihydroxy benzene
(c) 1, 3, 5 – trihydroxy benzene
(d) 1, 2, 3 – trihydroxy benzene
Answer:
(c) 1, 3, 5 – trihydroxy benzene

Question 80.
The other name of 1 , 2, 3 – trihydroxy benzene is called ……….
(a) Pholoroglucinol
(b) Quinol
(c) Pyrogallol
(d) Hydroxy quinol
Answer:
(c) Pyrogallol

Question 81.
The other name of 3, 5 – dihydroxy toluene is known as …………
(a) Orcinol
(b) Quinol
(c) Pyrogallol
(d) Resorcinol
Answer:
(a) Orcinol

Question 82.
The IUPAC name of Catechol is known as ………..
(a) 1 , 3 – dihydroxy benzene
(b) 1, 2 – dihydroxy benzene
(c) 1, 4 – dihydroxy benzene
(d) 1, 3, 5 – trihydroxy benzene
Answer:
(b) 1, 2 – dihydroxy benzene

Question 83.
The name of

is …………
(a) Phloroglucinol
(b) pyrogallol
(c) Quinol
(d) Resorcinol
Answer:
(a) Phloroglucinol

Question 84.
The name of

(a) Pyrogallol
(b) Hydroxy cresol
(c) Orcinol
(d) Phloroglucinol
Answer:
(c) Orcinol

Question 85.
The reaction of chiorobenzene with NaOH is known as ………..
(a) Kolbe’s reaction
(b) Riemcr – Ticmann reaction
(c) Dow’s process
(d) Cumene synthesis
Answer:
(c) Dow’s process

Question 86.
Which one of the product is formed when benzene and propene is heated at 523 K?
(a) Cumene
(b) 2 – ethyl benzene
(c) 2 – propyl benzene
(d) Ethyl enthanoate
Answer:
(a) Cumene

Question 87.
What will be the product formed when phenol is treated with zinc dust?
(a) Cumene
(b) Toluene
(c) Ethyl benzene
(d) Benzene
Answer:
(d) Benzene

Question 88.
The acetylation and benzoylation of phenol are called ……….
(a) Dow’s process
(b) Schotten – Baumann reaction
(c) Reimer – Tiemann reaction
(d) Williamson ether synthesis
Answer:
(b) Schotten – Baumann reaction

Question 89.
Name the product formed when phenol is heated with ammonia in the presence of anhydrous
ZnCl₂.
(a) Benzene
(b) Aniline
(c) Anisole
(d) Phenyl acetate
Answer:
(b) Aniline

Question 90.
What will be the product formed when phenol is treated with benzoyl chloride in the presence of a base?
(a) Phenyl acetate
(b) Phenyl cnthanoatc
(c) Phenyl benzoate
(d) Benzyl acetate
Answer:
(c) Phenyl benzoate

Question 91.
Which one of the following is formed when phenol istreated with acidified K₂Cr₂O₇?
(a) Benzoic acid
(b) Phenyl amine
(c) Phenyl acetate
(d) 1, 4 – benzo quinone
Answer:
(d) 1, 4 – benzo quinone

Question 92.
Hydrogenation of phenol in the presence of Nickel gives ………
(a) cyclo hexane
(b) cyclo hexanol
(c) benzene
(d) cumene
Answer:
(b) cyclo hexanol

Question 93.
Which one of the following is formed when phenol reacts with a mixture of Conc. HNO₃ and Conc.H₂SO₄?
(a) Ortho nitro phenol
(b) Para nitro phenol
(c) 1, 2 – dinitro phenol
(d) 2, 4 , 6 – trinitro phenol
Answer:
(d) 2, 4 , 6 – trinitro phenol

Question 94.
What will be the product formed when phenol reacts with bromine water?
(a) 0 – bromo phenol
(b) P – bromo phenol
(c) 1, 3, 5 – tri bromo phenol
(d) 2, 4, 6 – tri bromo phenol
Answer:
(d) 2, 4, 6 – tri bromo phenol

Question 95.
The conversion reaction of phenol of salicylic acid is known as
(a) Schottan – Baumann reaction
(b) Riemer – Ticmann reaction
(c) Kolbe’s Schmitt reaction
(d) Williamson’s synthesis
Answer:
(c) Kolbe’s Schmitt reaction

Question 96.
The reagent used for the conversion of phenol into salicylaldehyde is ………..
(a) CHCI₃ / NaOH
(b) I₂ / KOH
(c) Zn
(d) Br₂ / CCl₄
Answer:
(a) CHCI₃ / NaOH

Question 97.
What is the name of the reaction of phenol with chloroform and aqueous alkali?
(a) Kolbe’s reaction
(b) Cumene synthesis
(c) Rlemer – Tiemann reaction
(d) Schottan – Baumann reaction
Answer:
(c) Rlemer – Tiemann reaction

Question 98.
Which one of the following is formed when phenol is treated with chloroform and sodium hydroxide.
(a) Chiorobenzene
(b) Salicylaldehyde
(c) Salicylic acid
(d) Aniline
Answer:
(b) Salicylaldehyde

Question 99.
What are the reagents required to prepare phenolphthalein?
(a) Phenol + Phthalic acid
(b) Phenol + Benzene
(c) Phenol + Phthalic anhydride
(d) Phenol + Aniline
Answer:
(c) Phenol + Phthalic anhydride

Question 100.
Which one of the following is formed when Phenol reacts with benzene diazonium chloride?
(a) P – hyclroxy diazo phenol
(b) P – hydroxy azo benzene
(c) O – hydroxy benzene
(d) O – hydroxy azo benzene
Answer:
(b) P – hydroxy azo benzene

Question 101.
Which reagent gives purple colouration with phenol?
(a) Anhydrous AlCl₃
(b) Anhydrous ZnCl₂
(c) Neutral FeCI₃
(d) HCI + ZnCI₂
Answer:
(c) Neutral FeCI₃

Question 102.
Bakelite is formed when phenol reacts with ………..
(a) Methanol
(b) Methanal
(c) Ethanal
(d) Ethanol
Answer:
(b) Methanal

Question 103.
Which one of the following is used as an antiseptic – carbolic lotion and carbolic soaps?
(a) Benzyl alcohol
(b) Methanol
(c) Glycol
(d) Phenol
Answer:
(d) Phenol

Question 104.
The product formed when formaldehyde reacts with phenol is ……..
(a) Bakelite
(b) Phenolphthalein
(c) Azodye
(d) Aniline
Answer:
(a) Bakelite

Question 105.
Which one of the following is a simple ether?

Answer:

Question 106.
Which one of the following is an example for mixed ether?
(a) Methoxy methane
(b) Phenoxy benzene
(c) Methoxy benzene
(d) Ethoxy ethane
Answer:
(c) Methoxy benzene

Question 107.
The IUPAC name of

(a) 1 – methoxyl isopropyl ethane
(b) 2 – methoxy – 2 – methyl propane
(c) 2, 2 – dimethyl 2- methoxy ethane
(d) Methoxy tertiary butane
Answer:
(b) 2 – methoxy – 2 – methyl propane

Question 108.
The IUPAC name of C₆H₅ – O – C₆H₅ is ……..
(a) Diphenyl ether
(b) Phenoxy methane
(c) Phenoxy benzene
(d) Ethoxy benzene
Answer:
(c) Phenoxy benzene

Question 109.
Which one of the following is not a simple ether?
(a) C₆H₅ – O – CH₂ – CH₃
(b) CH₃ – O – CH₃
(c) C₆H₅ – O – C₆H₅
(d) C₂H₅ – O – C₂H₅
Answer:
(a) C₆H₅ – O – CH₂ – CH₃

Question 110.
What is the name of the reaction when ethanol is treated with Conc.H₂SO₄ at 413 K?
(a) Intermolecular dehydration
(b) Intra – molecular dehydration
(c) Dehydrogenation
(d) Dehydro halogenation
Answer:
(a) Intermolecular dehydration

Question 111.
Identify the product formed when ethanol is treated with Conc.H₂SO₄ at 413 K?
(a) Ethene
(b) Ethane
(c) 2 – butanol
(d) Diethyl ether
Answer:
(d) Diethyl ether

Question 112.
The reaction of sodium methoxide with ethyl bromide follows
(a) SN¹ mechanism
(b) SN² mechanism
(c) E₁ reaction
(d) E₂ reaction
Answer:
(b) SN² mechanism

Question 113.
The product formed when tertiary butyl bromide and sodium methode are react together is ……….
(a) 2 – methyl – 2 – methoxy propane
(b) ethoxy ethane
(c) 2 – methyl – prop – 1 – ene
(d) 2 – methyl but – 1 – ene
Answer:
(c) 2 – methyl – prop – 1 – ene

Question 114.
Identify the product formed when diazomethane reacts with Ethanol in the presence of HBF₄?
(a) Methoxy ethane
(b) Ethoxy ethane
(c) Diethyl ether
(d) Ethyl isopropyl ether
Answer:
(a) Methoxy ethane

Question 115.
What arc the products formed when methoxy ethanc is treated with hydroiodic acid?
(a) Phenol + iodomethane
(b) Todomethane + Ethanol
(c) lodoethane + Methanol
(d) lodobenzene + Methane
Answer:
(b) Todomethane + Ethanol

Question 116.
What are the products formed when methoxy benzene is treated with HI?
(a) C₆H₅OH + CH₄
(b) CH₃I + C₆H₆
(c) C₆H₅ OH + CH₃I
(d) C₂H₅I + C₆H₆
Answer:
(c) C₆H₅ OH + CH₃I

Question 117.
The mechanism involved in Williamson’s synthesis is …………
(a) E₁
(b) E₂
(c) SN²
(d) SN¹
Answer:
(c) SN²

Question 118.
When diethyl ether is exposed to excess oxygen, the reaction taken place is …………
(a) reduction
(b) hydrogenation
(c) dehydrogenation
(d) auto oxidation
Answer:
(d) auto oxidation

Question 119.
Which one of the following is formed when Diethyl ether is treated with dil.H₂SO₄?
(a) CH₃CH₂HSO₄
(b) CH₃ – CH₂OH
(c) CH₂ = CH₂
(d) CH₃ – CH₃
Answer:
(b) CH₃ – CH₂OH

Question 120.
Which one of the following is formed when diethyl ether reacts with Cl2 in the presence of light?

Answer:

Question 121.

In the above reaction A and B are
(a) CH₃ CH₂ OH + CH₃ – CH₂ Cl
(b) CH₃ – CH₂Cl + CH₃ COOH
(c) CH₃ COOH + CH₃ COOCH₃
(d) CH₃ – CH₂CI + CH₃COOCH₂CH₃
Answer:
(d) CH₃ – CH₂CI + CH₃COOCH₂CH₃

Question 122.
Anisole undergoes bromination with Br₂ in acetic acid in the absence of catalyst, the major product formed is ………..
(a) O – bromoan isole
(b) P – bromoan isole
(c) Benzyl bromide
(d) Bromo benzene
Answer:
(b) P – bromoan isole

Question 123.
Anisole reacts with methyl chloride in the presence of anhydrous AICI₃ and CS₂ to give ……..
(a) 2 – methoxy toluene
(b) 4 – methoxy toluene
(c) either (a) or (b)
(d) both (a) and (b)
Answer:
(d) both (a) and (b)

Question 124.
Which one of the following is used as a surgical anesthetic agent in surgery?
(a) Ethanol
(b) Ethoxy ethane
(c) Methoxy ethane
(d) Methoxy propane
Answer:
(b) Ethoxy ethane

Question 125.
Which one of the following is a precursor to the synthesis of perfumes and insecticide pheromones?
(a) Phenol
(b) Benzyl alcohol
(c) Anisole
(d) Diethyl ether
Answer:
(c) Anisole

Question 126.
Among the alkenes which one produces tertiary butyl alcohol on acid hydration?
(a) (CH₃)₂C CH₂
(b) CH₃ – CH = CH – CH₃
(c) CH₃ – CH₂ – CH = CH₂
(d) CH₃ – CH = CH₂
Answer:
(a) (CH₃)₂C CH₂

Question 127.
An ether is more volatile than an alcohol having the same molecular formula. This is due to
(a) dipolar character of ethers
(b) alcohols having resonance structures
(c) inter molecular hydrogen bonding in ethers
(d) inter molecular hydrogen bonding in alcohols
Answer:
(d) inter molecular hydrogen bonding in alcohols

Question 128.
An organic compound A containing C, H and O has a pleasant odour. On boiling A with Conc.H₂SO₄, a colourless gas is produced which decolourises bromine water and alkaline KMnO₄. The organic liquid A is ………..
(a) C₂H₅COOCH₃
(b) C₂HOH
(c) C₂H₅CI
(d) C₂H₆
Answer:
(b) C₂HOH

Question 129.
Chloroethane reacts with X to form diethyl ether. What is X?
(a) NaOH
(b) H₂SO₄
(c) C₂H₅ONa
(d) C₂H₅Cl
Answer:
(c) C₂H₅ONa

Question 130.
In the following sequence of reactions,

the compound D is ……….
(a) Butanal
(b) n-butyl alcohol
(c) propan – 1 – ol
(d) Propanal
Answer:
(c) propan – 1 – ol

Question 131.
Propan – 1 – ol and Propan – 2 – ol can be chemically distinguished by which reagent?
(a) PCI₅
(b) Reduction
(c) Oxidation with K₂ Cr₂0₇
(d) Ozonolysis
Answer:
(c) Oxidation with K₂ Cr₂0₇

Question 132.
Phenol can be distinguished from ethanol by the following reagents except
(a) Sodium
(b) NaOH / I₂
(c) Neutral FeCI₃
(d) Br₂ / H₂O
Answer:
(a) Sodium

Question 133.
in cold countries, ethylene glycol is added to water in the radiators to …………
(a) bring down the specific heat of water
(b) lower the viscosity
(c) reduce the viscosity
(d) make water a better lubricant
Answer:
(a) bring down the specific heat of water
(i.e.) lowering down the freezing point of water.

Question 134.
Main constituent of dynamite is ………..
(a) nitro benzene
(b) nitro glycerine
(c) Picric acid
(d) TNT
Answer:
(b) nitro glycerine

Question 135.
Diethyl ether finds use in medicine as …………
(a) a pain killer
(b) a hypnotic
(c) an antiseptic
(d) an anaesthetic
Answer:
(d) an anaesthetic

Question 136.
Benzene diazonium chloride on reaction with phenol in weakly basic medium gives
(a) Diphenyl ether
(b) P – hydroxy azo benzene
(c) Chlorobenzene
(d) Benzene
Answer:
(b) P – hydroxy azo benzene

Question 137.
The alcohol that produces turbidity immediately with ZnCl₂ + Conc.HCl at room temperature is ………..
(a) Rutan – 1- ol
(b) Butan – 2- ol
(c) 2 – methyl – propan – 1 – ol
(d) 2 – methyl – propan – 2 – ol
Answer:
(d) 2 – methyl – propan – 2 – ol

Question 138.
Propanone is the product obtained by dehydrogenation of …………
(a) Propan – 2 – ol
(b) Propan – 1 – ol
(c) Propanal
(d) n – propyl alcohol
Answer:
(a) Propan – 2 – ol

Question 139.
Which of the following statement is correct?
(a) Phenol is less acidic than ethanol
(b) Phenol is more acidic than ethanol
(c) Phenol is more acidic than carboxylic acid
(d) Phenol is less acidic than carboxylic acid
Answer:
(b) Phenol is more acidic than ethanol

Question 140.
The reaction of ethylene glycol with Pl₃ gives ………..
(a) CH₂ = CHI
(b) ICH₂ – CH₂I
(c) CH₂ = CH2₂
(d) CH = CH
Answer:
(a) CH₂ = CHI

Question 141.
During dehydration of alcohols to alkenes by heating with Conc. H₂SO₄ ,the initiation step is ………..
(a) protonatlon of alcohol
(b) formation of carbocation
(c) elimination of water
(d) formation of carbanion
Answer:
(a) protonatlon of alcohol

Question 142.
Sodium phenoxide reacts with CO₂ at 400 K and 4 – 7 bar pressure to give ………
(a) Sodium salicylate
(b) Salicylaldehyde
(c) Cate chol
(d) Pyrogallol
Answer:
(a) Sodium salicylate

Question 143.
The reaction of C₂ H₅OH with Cone. H₂ SO₄ does not give ………..
(a) Ethylene
(b) Diethyl ether
(c) Acetylene
(d) Ethyl hydrogen sulphate
Answer:
(c) Acetylene

Question 144.
Which of the following gives ketone on oxidation?

Answer:

Question 145.
Phenol is treated with Br₂ /H₂O and shaken well. The white precipitate formed during the process is …………
(a) m – bromo phenol
(b) 2,4 – dibromo phenol
(c) 2, 4, 6 – tribromo phenol
(d) 1, 2 – dibromo benzene
Answer:
(c) 2, 4, 6 – tribromo phenol

Question 146.
Which compound has the highest boiling point?
(a) Acetone
(b) Diethyl ether
(c) Methanol
(d) Ethanol
Answer:
(d) Ethanol

Question 147.
When phenol reacts with NH₃ in the presence of ZnCl₂ at 300°C, it gives ………..
(a) 1° amine
(b) 2° amine
(c) 3° amine
(d) Both (b) and (c)
Answer:
(a) 1° amine

Question 148.
Azo dyes are prepared from …………
(a) Aniline + Phenol
(b) Phenol + Phthalic anhydride
(c) Phenol + Benzene diazonium chloride
(d) Aniline + Phthalic anhydride
Answer:
(c) Phenol + Benzene diazonium chloride

Question 149.
A compound that easily undergoes bromination is ………….
(a) Phenol
(b) Toluene
(c) Benzene
(d) Diethyl ether
Answer:
(a) Phenol

Question 150.
When glycerol is treated with P₂O₅ (or) KHSO₄ the product formed is ……….
(a) CH₂ = CH – CH₃
(b) CH₂ = CH – CH₂OH
(c) CH₂ = CH – CHO
(d) CH₂ = C = CH₂
Answer:
(c) CH₂ = CH – CHO

Question 151.
The ether that undergoes electrophilic substitution reactions is ………….
(a) CH₃ – O – C₂H₅
(b) C₆H₅ – O – CH₃
(c) C₂H₅ – O – C₂H₅
(d) CH₃ – O – CH₃
Answer:
(b) C₆H₅ – O – CH₃

Question 152.
With anhydrous ZnCl₂, ethylene glycol gives …………
(a) Formaldehyde
(b) Acetylene
(c) Acetaldehyde
(d) Dioxan
Answer:
(c) Acetaldehyde

Question 153.
Fats on alkaline hydrolysis give …………
(a) Oil + Soap
(b) Soap + Glycol
(c) Soap + Ester
(d) Soap + Glycerol
Answer:
(d) Soap + Glycerol

Question 154.

B. in this reaction A and B are respectively
(a) Alkene, Alkyne
(b) Alkanal, Alkene
(c) Alkyne, Alkanal
(d) Alkyne, Alkene
Answer:
(b) Alkanal, Alkene

Question 155.
Oxygen atom in ether is …………
(a) very active
(b) replacable
(c) comparatively inert
(d) less active
Answer:
(c) comparatively inert

Question 156.
Chlorination of toluene in the presence of light and heat followed by treatment with aqueous NaOH gives ………….
(a) O – cresol
(b) P – cresol
(c) Phioroglucinol
(d) Benzyl alcohol
Answer:
(c) Phioroglucinol

Question 157.
Primary alcohols can be obtained from the reaction of RMgX with …………
(a) CO₂
(b) HCHO
(c) CH₃CHO
(d) H₂O
Answer:
(b) HCHO

Question 158.
The dehydration of alcohol is an example of ………….
(a) Bimolecular elimination reaction
(b) Nucleophilic substitution reaction
(c) Unimolecular elimination reaction
(d) internal substitution reaction
Answer:
(c) Unimolecular elimination reaction

Question 159.
Ethanol is converted into Ethoxy ethane ………….
(a) by heating with cone. H₂SO₄ at 443 K
(b) by heating with conc. H₂SO₄ at 413 K
(c) by heating with excess oxygen
(d) by heating with hydrogen
Answer:
(b) by heating with conc. H₂SO₄ at 413 K

Question 160.
Which of the following is not the product of dehydration of


Answer:

II. Fill in the blanks

1. Cholesteryl alcohol commonly known as …………. is an important component in our ………….
2. …………. the storage form of vitamin A, finds application in proper functioning of our eyes.
3. Methanol s used as an …………. solvent.
4. Isopropyl alcohol is used as …………. for injection.
5. CH₂CHOH is called as ………….
6. An example of hexahydric alcohol is ………….
7. The IUPAC name of glycerol is ………….
8. The TUPAC name of Neopentyl alcohol is ………….
9. The TUPAC name of CH₂ CH – CHOH is ………….
10. In methanol, the – OH group attached to …………. hybridised carbon atom.
11. The bond angle C – OH in methanol is ………….
12. alkyl halides undergo substitution by SN² reaction whereas …………. and …………. alkyl halides undergo substitution by SN¹ reaction.
13. Addition of H₂O to an unsymmetric alkene in the process of sulphuric acid follows ………….
14. Nucleophilic addition of Grignard reagent to aldehydes/ketones take place in the presence …………. followed by acid hydrolysis gives .
15. With RMgx …………., …………. gives l°alcohol.
16. Butyl Magnesium bromide reacts with propanone to give ………….
17. …………. is used to prepare a secondary alcohol with identical group.
18. Hydroboration yields an …………. product.
19. …………. is the best reagent to prepare unsaturated alcohol by reduction reaction of carbonyl compound.
20. …………. occurs in natural fats and in long chain fatty acids in form of triglycerides.
21. The alkaline hydrolysis of fats gives glycerol and the reaction is known as ………….
22. In Lucas test …………. alcohol do not react at room temperature.
23. In Victor Meyer’s test no colouration will be observed in case of ………….
24. Alkyl halide formation from primary alcohol follows …………. mechanism.
25. Alkyl halide formation from tertiary alcohol follows …………. mechanism.
26. The reaction between methanol and thionyl chloride in the presence of pyridine follows…………. mechanism.
27. …………. alcohols undergo dehydration by E₂ mechanism whereas alcohols undergo dehydration by E₁ mechanism.
28. To stop the oxidation reaction of alcohol at aldehyde / ketone stage …………. is used as an oxidising agent.
29.  In …………. oxidation dimethyl sulfoxide (DMSO) is used as an oxidising agent.
30. The fermentation of food consumed by an animal produces …………..
31. The detoxify the alcohol, the liver produces an enzyme called ………….
32. …………. present in the animals act as an oxidising agent and …………. catalyses the oxidation of toxic alcohol into non-toxic aldehydes.
33. Ethylene glycol, when heated to 773 K, it forms ………….
34. The reagent used to convert ethane 1, 2 -diol to ethanal is ………….
35. When Ethane – 1, 2 -diol is treated with conc.H₂S0₄, it forms ………….
36. The intermediate product formed when ethylene glycol is treated with periodic acid is ………….
37. The final product formed when glycol reacts with periodic acid is ………….
38. The IUPAC name of Acrolein (or) CH₂ = CH – CHO is ………….
39. Oxidation of glycerol with dilute nitric acid gives …………. and ………….
40. Oxidation of glycerol with bismuth nitrate gives ………….
41. Oxidation of glycerol with Fenton’s reagent gives ………….
42. LTA is known as ………….
43. Oxidation of glycerol with acidified KMnO₄ gives ………….
44. FeSO₄ + H₂O₂ is called ………….
45. …………. is used as a substitute for petrol under the name and used as fuel for aeroplane.
46. …………. is used as an anti-freezer in automobile radiators.
47. …………. is used as a sweetening agent in confectionery and beverages.
48. …………. is used in the manufacture of transparent soap, printing ink and stamp pad ink.
49. Glycerol is used in the manufacture of explosives like and by mixing with ………….
50. Except …………. all other alcohols are weaker acid than water.
51. The electron withdrawing groups such as – NO₂, – Cl enhances the acidic nature of phenol especially when they are present at …………. positions.
52. The LUPAC name of hydroxy quinol is ………….
53. The IUPAC name of orcinol is ………….
54. The other name of 1, 2, 3 – trihydroxy benzene is ………….
55. The reaction of chioro benzene with aqueous NaOH to give phenol is known as ………….
56. The product formed when benzene diazonium chloride is boiled with hot water is ………….
57. The IUPAC name of curnene is ………….
58. Phenol is converted to benzene on heating with ………….
59. The acetylation and benzoylation of phenol are called ………….
60. The reagent used in the conversion of phenol to 1, 4 – benzo quinone is ………….
61. When phenol is treated with Conc.HNO₃ and Conc.H₂SO₄, the product formed is ………….
62. Phenol reacts with bromine water to give a precipitate of ………….
63. The conversion reaction of phenol to salicylic acid is known as ………….
64. The conversion reaction of phenol into salicylaldehyde is known as ………….
65. The product formed when phenol is treated with phthalic anhydride in the presence of Conc.H₂SO₄ is ………….
66. …………. dye is Ibmied when phenol couples with benzene diazonium chloride in an alkalin
    solution.
67. Phenol gives …………. colouration with neutral FeCI₃.
68. Phenol formaldehyde is known as ………….
69. The IUPAC name of tertiary butyl methyL ether is known as ………….
70. C₆H₅O – CH₂ – CH₃ is known as ………….
71. The mechanism take place when alkyl halide is treated with alcohol solution of sodiunalkoxide is ………….
72. The dipole moment of diethyl ether is ………….
73. The reaction take place when ethers are exposed to oxygen is ………….
74. …………. is used as a surgical anesthetic agent in surgery.
75. …………. is used as refrigerant.

Answer:

1. cholesteroL, cell membrane
2. Retinol
3. industrial
4. skin cleanser
5. vinyl alcohol (or) ethenol
6. Sorbitol
7. propan – 1, 2, 3 – tnol,
8.  2, 2 – ditnethyl propan – 1 – ol
9. prop – 2 – en – 1 – ol
10. sp³
11. 108.9°
12. 1°, 2°, 3°
13. Markownikoff’s rule
14. dry ether, alcohol
15. formaldehyde, HCHO
16. 2-methyl hexan – 2 – ol
17. Formate ester
18. Anti-Markownikoft’s
19. LiAlH₄
20. Glycerol
21. Saoinufucatuib
22. Primary
23. Tertiary alcohol
24. SN²
25. SN¹
26. SN²
27. Pnmary, Tertiary
28. pyridinium chlorochromate
29. Swer
30. alcohol
31. alcohol dehydrogenase ALH
32. NAD,ADH
33. epoxide (or) 1,2-epoxy ethane (or) oxirane
34. dil.H₂SO (or) anhydrous ZnCI₂
35. 1,4 – dioxane
36. cyclic periodate ester
37. formaldehyde
38. prop – 2 – enal
39. glycenc acid, Tartronic acid
40. Meso oxalic acid
41. glycerose (or) a mixture of glyceraldehyde and dihydroxy acetone
42. Lead tetra acetate
43. Oxalic acid
44. 44. Fenton’s reagent
45. Ethanol, Power alcohol
46. Ethylene glycol
47. Glycerol
48. Glycerol
49. dynamite, cordite, china clay
50. Methanol
51. ortho and para
52. 1, 2, 4 – trihydroxy benzene
53. 3, 5 – dihydroxy toluene
54. Pyrogallol
55. Dows process
56. Phenol
57. 2 – phenyl propane
58. Zinc dust
59. Schotten-Baumann reaction
60. acidified K₂Cr₂O₇
61. 2,4, 6 – trinitro phenol (or) Picric acid
62. white, 2,4, 6-tribromo phenol
63. Kolbe’s Schmitt reaction
64. Riemer-Tiemann Reaction
65. Phenol phthalein
66. P-hydroxy azo benzene (or) Red orange dye
67. Purple
68. Bakelite
69. 2-methoxy – 2 – methyl propane
70. Phenatole (or) Ethoxy benzene
71. SN²
72. 1.18 D
73. auto oxidation
74. Diethyl ether
75. Diethyl ether

III. Match the following Colum – I with Column – II ysubg tge cide guveb below.

Question 1.

Answer:
(a) 3 4 1 2

Question 2.

Answer:
(a) 2 4 1 3

Question 3.

Answer:
(c) 4 3 2 1

Question 4.

Answer:
(a) 3 1 4 2

Question 5.

Answer:
(b) 4 3 1 2

Question 6.

Answer:
(a) 3 1 4 2

Question 7.

Answer:
(a) 3 1 4 2

Question 8.

Answer:
(a) 2 3 4 1

Question 9.

Answer:
(a) 3 4 1 2

Question 10.

Answer:
(a) 2 3 4 1

Question 11.

Answer:
(a) 3 1 4 2

Question 12.

Answer:
(a) 2 3 4 1

Question 13.

Answer:
(a) 2 3 4 1

Question 14.

Answer:
(a) 4 1 2 3

Question 15.

Answer:
(a) 3 1 4 2

Question 16.

Answer:
(a) 4 1 2 3

Question 17.

Answer:
(a) 4 3 1 2

IV. Assertion and reasons.

Question 1.
Assertion(A): P – nitro phenol is having lower pK_a value than phenol.
Reason (R): The electron with drawing group – NO₂ at para position enhances the acidic nature.
(a) Both A and R are correct and R is the correct explanation of A.
(b)BothAand Rare wrong
(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 2.
Assertion(A): Alcohols cannot be used as solvent for Grignard reagent.
Reason (R): Alcohols are decomposed by Grignard reagents to give alkane.
(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 correct but R is not correct explanation of A.
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 3.
Assertion(A): Phenols are soluble in alcohols.
Reason (R): Phenols are soluble in alcohol due to the formation of inter molecular hydrogen bonding.
(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): Phenol is insoluble in NaHCO₃ solution but acetic acid is soluble.
Reason (R): Phenols are weakly acidic and hence they dissolve only in strong base and insoluble in weak base like NaHCO₃. But acetic acid is a stronger acid than phenol and so it is soluble in weak base NaHCO₃.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and 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 5.
Assertion(A): Glycol is more viscous than ethanol.
Reason (R): Glycol contains two hydroxyl groups and the inter molecular hydrogen bonding is made much stronger resulting in a polymeric structure. This leads to high viscosity than ethanol.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and 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): Ethanol is a weaker acid than Phenol.
Reason (R): Sodium ethoxidc may be prepared by the reaction of ethanol with sodium metal but phenol reacts with NaOH.
(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 7.
Assertion(A): Both alcohol and ether have higher boiling point.
Reason (R): Both are having intermolecular hydrogen bonding.
(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:
(b) Both A and R are wrong

Question 8.
Assertion(A): Bond angle in ethers is slightly less than the tetra hedral angle.
Reason (R): There is a repulsion between the two bulkier R groups.
(a) Both A and R are correct but R is not the correct explanation of A.
(b) Both A and arc wrong
(c) Both A and R are correct and R is the correct explanation of A.
(d) A is correct but R is wrong
Answer:
(c) Both A and R are correct and R is the correct explanation of A.

Question 9.
Assertion(A): P-nitro phenol is a stronger acid than o – nitro phenol.
Reason (R): Intra molecular hydrogen bonding in o – nitro phenol make it as a weaker acid.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and 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 10.
Assertion(A): Phenol is more reactive towards electrophilic substitution reaction.
Reason (R): In the case of phenol, the intermediate carbo cations is more resonance stabilized.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and 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 11.
Assertion(A): Phenol forms 2, 4, 6 – tribromo phenol on treatment with Br₂ in CS₂ at 273 K.
Reason (R): Bromine polarizes in CS₂.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and are incorrect
(c) A is correct but R is wrong
(d) A is wrong but R is correct
Answer:
(b) Both A and are incorrect

Question 12.
Assertion(A): Phenol is more acidic than ethanol.
Reason (R): Phenoxide ion is more stable than ethoxide due to resonance.
(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): Boiling point of ethanol is higher in comparison to methoxy methane.
Reason (R): Ethanol is associated with inter molecular hydroxide bonding whereas in methoxy methane, inter molecular hydrogen bonding is not present.
(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 not 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): (CH₃)₃ C – O – CH₃ on reaction with HI gives CH₃OH and (CH₃)₃C – I as the main products and not (CH₃)₃ C – OH and CH₃I.
Reason (R): (CH₃)₃ C + (Tertiary carbo cation) is more stable and reacts with HI to form (CH₃)₃ C – I as main product.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and 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 15.
Assertion(A): The bond angle (C – O – H) in methanol is reduced to 108.9° from the regular tetra hedral bond angle of 109.5°.
Reason (R): In methanol, two lone pairs of electrons are present in oxygen atom and due to lone pair – lone pair repulsion, the bond angle is reduced.
(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 16.
Assertion(A): LiAlH₄ is the best reagent to prepare unsaturated alcohols from carbonyl compounds.
Reason (R): LiAlH₄ does not reduce the carbon – carbon double bond present in the carbonyl carbon compound.
(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 17.
Assertion(A): Primary alcohols are more acidic than tertiary alcohol.
Reason (R): Alkyl groups (electron releasing group) increases the electron density on oxygen and decreases the polar nature of – OH bond. Hence it results in the decrease in acidity.
(a) Both A and R are correct and R is the correct explanation of 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 the correct explanation of A.

Question 18.
Assertion(A): P – cresol is less acidic than phenol.
Reason (R): Alkyl substituted phenols show a decreased acidity due to the electron releasing + I effect of alkyl group.
(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) 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 19.
Assertion(A): O – nitro phenol is slightly soluble in water whereas P – nitro phenol is more soluble in water.
Reason (R): O – nitro phenol has intra molecular hydrogen bonding whereas P – nitro phenol has inter molecular hydrogen bonding.
(a) Both A and R are correct and R is the correct explanation of A.
(b) Both A and are wrong
(c) A is correct but R is wrong
(d) A is wiong but R is correct
Answer:
(a) Both A and R are correct and R is the correct explanation of A.

Question 20.
Assertion(A): Inter molecular dehydration of alcohol is not a suitable method of prepare mixed ethers.
Reason (R): When a mixture of two different alcohols are used, mixture of different ethers are formed and they are difficult to separate.
(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.

Samacheer Kalvi 12th Chemistry Hydroxy Compounds and Ethers 2 Mark Questions and Answers

V. Answer the following

Question 1.
Write the molecular formula and IUPAC name of the following compounds.

1. Vinyl alcohol
2. Sorbitol

Answer:
1. Vinyl alcohol
CH₂ = CHOH
IUPAC name: Ethenol

2. Sorbitol
HO – CH₂ – (CHOH)₄ – CH₂OH
IUPAC name : Hexan – 1, 2, 3, 4, 5, 6 – hexol

Question 2.
Write the structural formula of the following compounds.

1. Prop – 2 – en – 1 – ol
2. Prop – 3 – en – 1 – ol

Answer:
1. Prop – 2 – en – 1 – ol : CH₂ = CH – CH₂OH

2. Prop – 3 – en – 1 – oI :

Question 3.
Write the structural formula of the following compound.

1. Phenyl methanol
2. 2 – methyl – but – 3 – en – 2 – ol

Answer:
1. Phenyl methanol : C₆H₅ – CH₂OH

2. 2 – methyl – but – 3 – en – 2 – ol :

Question 4.
Write the possible isomers for the formula

1. C₂H₆O
2. C₃H₈O

Answer:
1. C₂H₆O

2. C₃H₈O
(a) CH₃ CH₂ – CH₂ OH : Propan – 1 – ol

(b)
Propan – 1 – ol

(a) and (b) – Position isomerism
(a) and (c) – Functional isomerism

Question 5.
Explain about the structure of methanol.
Answer:
1. In methanol, one of the sp³ hybridised orbital of oxygen linearly overlap with the sp³ hybridised orbital of carbon to form a C – O, a bond and another sp³ hybridised orbitai linearly overlap with 1s orbital of hydrogen atom to form a O – H a bond.

2.

3. The remaining two sp3 hybridised orbitais of oxygen are occupied by two lone pairs of electrons. Due to the lone pair – lone pair repulsion, the C – O – H bond angle in methanol is reduced to 108.9° from the regular tetrahedral bond angle of 109.5°.

Question 6.
Convert phenyl magnesium bromide to phenyl methanol (or) How would you prepare phenyl methanol from Grignard reagent?
Answer:

Question 7.
How will you prepare Butan-2-ol from ethanal? (or) Convert Ethyl Magnesium bromide into 2 – Butanol (or) Starting from acetaldehyde, how would you obtain butan – 2 – ol?
Answer:

Question 8.
Convert propanone into 2 – methyl – propan – 2 – ol.
Answer:

Question 9.
Starting from butyl magnesium bromide, how would you obtain 2 – methyl bexan – 2 – ol?
Answer:

Question 10.
What happens when methyl magnesium bromide reacts with ethl methanoate followed by acid hydrolysis?
Answer:

Question 11.
LiAlH₄ is a best reagent to prepare unsaturated alcohol. Prove it.
Answer:
LiAIH₄(Lithium Aluminium Hydride) does not reduce the carbon – carbon double bond present in the carbonyl compound and hence it is the best reagent to prepare unsaturated alcohol.

Question 12.
Convert acetone into propan – 2 – ol.
Answer:

Question 13.
How would you get Benzyl alcohol from Benzoic acid.
Answer:

Question 14.
Starting from ethyl ethanoate, how would you prepare ethanol?
Answer:

Question 15.
How will you prepare 4 – alkyl – 4 – hydroxy butanoic acid?
Answer:
When two or more functional groups are present in a molecule a less vigorous sodium borohydride is used as a reducing agent to reduce the more reactive group. For example, if a compound contains both carbonyl and carboxyl group, NaBH₄ reduces the carbonyl group.

Question 16.
What is saponification? Explain with equation.
Answer:
The alkaline hydrolysis of fats gives glycerol and soap then the reaction is known as saponification.

Question 17.
What happens when thionyl chloride is treated with methanol?

The above reaction follows SN² mechanism in the presence of pyridine.

Question 18.
Answer:
1. In Swern oxidation method, dimethyl sulfoxide (DMSO) is used as the oxidising agent and it converts alcohols to ketones / aldehydes.

2. When propan – 2 – ol is treated with DMSO and oxalyl chloride followed by the addition of triethylamine, it produces Propanone.

Question 19.
Explain biological oxidation with an example.
Answer:
Biological oxidation is the fermentation of the food consumed by an animal produces alcohol. To detoxify the alcohol, the liver produces an enzyme called alcohol dehydrogenase (ADH). Nicotinamide adenine dinucleotide (NAD) present in the animals acts as a oxidising agent and ADH catalyses the oxidation of toxic alcohols into non-toxic aldehyde.

Question 20.
What is esterificatloin? Explain with equation.
Answer:
Alcohols react with carboxylic acids in the presence of an acid to give esters. This reaction is known as Esterification.

Question 21.
How would you convert ethylene glycol into ethene?
Answer:

Question 22.
Explain the action of conc.HNO₃ and conc.H₂SO₄ with ethan – 1, 2 – diol.
Answer:

Question 23.
What happens when ethylene glycol is treated with periodic acid?
Answer:
Ethylene glycol on treatment with periodic acid gives formaldehyde. This reaction is selective for vicinal 1, 2 – diols and it proceeds through a cyclic periodate ester intermediate.

Question 24.
How is glycerol reacts with fuming nitric acid? (or) How would you convert glycerol into nitroglycerine?
Answer:

Question 25.
What happens when conc.H₂SO₄ or KHSO₄ is heated with glycerol?
Answer:
Dehydration:

Question 26.
Mention the uses of methanol.
Answer:

1. Methanol is used as a solvent for paints, varnishes, shellac, gums, cement, etc.
2. Methanol is used in the manufacture of dyes, drugs, perfumes and formaldehyde.

Question 27.
What are the uses of ethylene glycol?
Answer:

1. Ethylene glycol is used as an antifreeze in automobile radiator
2. Its dinitrate is used as an explosive with DNG.

Question 28.
Write a note about acidity of aliphatic alcohols.
Answer:
1. According to Bronsted theory, an acid is defined as a proton donor and the acid strength is the tendency to give up a proton. Alcohols are similarly acidic when compared with water. Except methanol, all other alcohols are weaker acid than water. The K_a value for water is 1.8 x 10^-16 where as for alcohols the Ka value in the order 10^-18 to 10^-16.

2. 2C₂H₅ – OH + 2Na → 2C₂H₅ONa + H₂ ↑
This reaction explains the acidic nature of alcohol as it liberates H₂ gas with Na metal.

Question 29.
Alcohol can act as Bronsted base. Prove this statement.
Answer:
Alcohols can also act as a Bronsted bases. It is due to the presence of unshared electron pairs on oxygen which make them to accept proton. So proton acceptor are Bronsted bases. i.e., alcohols are Bronsted bases.

Question 30.
What are cresols? Give examples.
Answer:
Methyl Phenols are called cresols.
They are

Question 31.
How is phenol obtained from benzene suiphonic acid?
Answer:

Question 32.
How is Aniline converted into Phenol?
Answer:
Aniline is diazotized with nitrous acid (NaNO₂ + HCI ) at 273 – 278K to give benzene diazonium chloride which on further treatment with hot water in the presence of mineral acid gives phenol.

Question 33.
How will you convert phenol into benzene?
Answer:
Phenol is converted to benzene on heating with Zinc dust.

Question 34.
What happens when phenol is heated with NH₃?
Answer:

Question 35.
What happens when phenol is heated with acidified K₂Cr₂O₇?
Answer:

Question 36.
How is phenol treated with Nickel?
Answer:

Question 37.
O – nitro phenol is slightly soluble ¡n water where as P-nitro phenol is more soluble. Cive reason.
Answer:
O-nitro phenol is slightly soluble in water and more volatile due to intra molecular hydrogen bonding, whereas P-nitro phenol is more soluble in water and less volatile due to intermolecular hydrogen bonding.

Question 38.
Explain Reimer Tiemann reaction.
Answer:
On treating phenol with CHCl₃ / NaOH, a – CHO group is introduced at ortho position. This reaction proceeds through the formation of substituted benzal chloride intermediate.

Question 39.
How is phenolphthalein prepared from phenol?
Answer:
On heating phenol with phthalic anhydride in presence of con.H₂SO₄, phenolphthalein is obtained,

Question 40.
What is Coupling reaction? Give equation.
Answer:
Phenol couples with benzene diazonium chloride in an alkaline solution to form p-hydroxy azobenzene(a red orange dye).

Question 41.
Write a note about the structure of ethereal oxygen.
Answer:
The structure of ethereal oxygen which is attached to two alkyl groups is similar to the structure of – OH group of alcohol. The oxygen atom is sp³ hybridized. Two sp³ hybridized orbitals of oxygen linearly overlap with two sp³ hybrid orbitais of the carbon which are directly attached to the oxygen forming two
C – O ‘σ’ bonds.

The C – O – C bond angle is slightly greater than the tetrahedral bond angle due to the repulsive interaction between the two bulkier alkyl groups.

Question 42.
Write the structure and common name of

1. Ethoxy benzene
2. Phenoxy benzene

Answer:
1. C₆H₅ – O – CH₂ – CH₃ : Ethoxy benzene (or) Phenetole (or) Ethyl phenyl ether

2. C₆H₅ – O – C₆H₅ : Phenoxy benzene (or) Diphenyl ether (or) Phenyl ether

Question 43.
What happens when ethanol reacts with conc. H₂SO₄ Sulphuric acid at 413 K?
Answer:
When ethanol reacts with con.H₂SO₄ at 413 K, inter molecular dehydration take place and diethyl ether is formed as product.

Question 44.
Explain the action of diazomethane with ethanol.
Answer:
Methyl ethers can be prepared when ethanol is treated with diazomethane in presence of fluoro boric acid.

Question 45.
Ether are miscible with water. Justify this statement.
Answer:
1. Oxygen of ether can also form Hydrogen bond with water and hence they are miscible with water.

2. Ethers dissolve wide range of polar and non-polar substances.

Question 46.
Ether bottle should not be kept open. Why?
Answer:
1. When ether bottle is kept open, they are exposed to atmospheric oxygen and slowly oxidised to form hydroperoxides and dialkyl peroxides. These are explosive in nature. Such a spontaneous oxidation by atmospheric oxygen is called autooxidation.

Question 47.
Explain the action of hydrogen iodide with anisole (or) methoxy benzene. –
Answer:

Question 48.
What are the uses of anisole?
Answer:

1. Anisole is a precursor to the synthesis of perfumes and insecticide pheromones,
2. It is used as a pharmaceutical agent.

Question 49.
Alcohols are comparatively more soluble in water than hydrocarbons of comparable molecular masses. Explain this fact.
Answer:
Alcohols can form H-bond with water molecules and break the H-bond already existing between the water molecules. Therefore, they are soluble in water.

On the other hand hydrocarbons do not have the ability to form H-bond with water molecules. Hence they are insoluble in water.

Question 50.
Explain why is ortho nitrophenol more acidic than ortho methoxyphenol?
Answer:
Ortho nitrophenol is more acidic than ortho methoxyphenol because nitro group is an electron withdrawing and it will increase +ve charge on the oxygen atom to make it more acidic whereas – OCH₃ group is an electron releasing group and it will decrease +ve charge on the oxygen atom, thus making it less acidic and hence the O – H bond will not break easily.

Question 51.
Give reason for the higher boiling point of ethanol in comparison to methoxymethane.
Answer:
Ethanol undergoes intermolecular H-bonding due to the presence of a hydrogen atom attached to the electronegative oxygen atom. As a result, ethanol exists as associated molecules.

Consequently, a large amount of energy is required to break these hydrogen bonds. Therefore, the boiling point of ethanol is higher than that of methoxymethane which does not form H-bonds.

Question 52.
What happens when phenol is treated with ¡ce cold bromine dissolved in CS₂?
Answer:

Question 53.
What happens when phenol is treated with excess of nitrating mixture? (Give equation only).
Answer:

Question 54.
Describe the mechanism by which the hydroxyl group attached to an aromatic ring is more acidic than the hydroxyl group attached to an alkyl group. How does the presence of nitro group in phenol affects its acidic character?
Answer:
1. The reaction of phenol with aqueous sodium hydroxide solution indicates that phenol is a stronger acid than alcohols in water.

2. Because phenoxide ion formed is stabilised by resonance whereas alkoxide ion formed is destabilised by positive inductive effect of alkyl group.

3. Presence of electron withdrawing group such as nitro group enhances the acidic strength of phenol. lt is due to the effective delocalisation of the negative charge in phenoxide ion.

Question 55.
Give two reactions that show the acidic nature of phenol. Compare the acidity of phenol with that of ethanol.
Answer:

Samacheer Kalvi 12th Chemistry Hydroxy Compounds and Ethers 3 Mark Questions and Answers

VI. Answer the following questions.

Question 1.
Give one example for each of the following with their structure and IUPAC name.

1. 1° alcohol
2. 2° alcohol
3. 3° alcohol

Answer:

Question 2.
Write the structure of the following compounds.

1. Phenyl methanol
2. 1 – Phenyl ethanol
3. 2 – Phenyl propan – 2 – ol

Answer:

Question 3.
Write the structures and IUPAC names of the following compounds.

1. Tertiary butyl alcohol
2. Neopentyl alcohol
3. Isobutyl alcohol

Answer:
1.
2 – methyl propan – 2 – ol (Tertiary butyl alcohol)

2.
2, 2 – dimethyl propan – 1 – ol (Neopentyl alcohol)

3.
2 – methyl propan – 1- ol (Isobutyl alcohol)

Question 4.
Draw the structures and write the IUPAC name of the following compounds.

1. Benzyl alcohol
2. Allyl alcohol
3. Cyclohexyl alcohol

Answer:
1.
Phenyl methanol (Benzyl alcohol)

2. CH₂ = CH – CH₂OH  Prop – 2 – en – 1 – ol (Allyl alcohol)

3.
Cyclo hexanol (Cyclohexyl alcohol)

Question 5.
Describe Lucas test used to distinguish Primary, Secondary and Tertiary alcohols.
Answer:
When alcohols are treated with Lucas agent (conc. HCI + anhydrous ZnCl₂) at room temperature, tertiary alcohols react immediately to form a turbidity due to the formation of alkyl chloride which is insoluble in the medium. Secondary alcohols react within 10 minutes to form a turbidity of alkyl chloride where primary alcohols do not react at room temperature.

Question 6.
Explain the mechanism of the reaction of alkyl halide formation from primary alcohol.
Answer:

Question 7.
Explain SN¹ mechanism of Tertiary alcohols reaction with HBr.
Answer:

Question 8.
Explain the mechanism involved in the reaction of phosphorous trichloride with Ethanol. SN² reaction of Ethanol with PCl₃
Answer:

Question 9.
Describe Saytzeff’s rule with example.
Answer:
1. During intramolecular dehydration, if there is a possibility to form a carbon – carbon double bond at different locations, the preferred location is the one that gives the more (highly) substituted alkene i.e., the stable alkene.

2. For example, the dehydration of 3, 3 – dimethyl – 2 – butanol gives a mixture of alkenes. The secondary carbocation formed in this reaction undergoes rearrangement to form a more stable tertiary carbocation.

Question 10.
Explain the following reactions.

Answer:

Question 11.
Explain about catalytic dehydrogenation of 1⁰, 2⁰ and 3⁰ alcohols
Answer:

Question 12.
Describe about the oxidation reaction of ethylene glycol with dilute nitric acid.
Answer:
When dilute nitric acid (or) alkaline KMnO₄ is used as the oxidizing agent, the following products are formed.

Question 13.
Explain about the oxidation reaction of Glycerol with different oxidising reagents.
Answer:

1. Oxidation of glycerol with dii. FINO₃ gives glyceric acid and tartronic acid.
2. Oxidation of glycerol with Conc. HNO₃ gives mainly glyceric acid.
3. Oxidation of glycerol with bismuth nitrate gives as meso oxalic acid.
4. Oxidation of glycerol with Br₂ /H₂O (or) NaOBr (or) Fenton reagent (FeSO₄ + H₂O₂)
5. gives a mixture of glyceraldehyde and dihydroxy acetone(glycerose).
6. On oxidation with HIO₄ or Lead tetra acetate (LTA) it gives formaldehyde and formic acid.
7. Acidified KMnO₄ oxidises glycerol into oxalicacid.

Question 14.
What are the uses of ethanol.
Answer:

1. Ethanol is used as an important beverage.
2. It is also used in the preparation of
   • Paints and varnishes
   • Organic compounds like ether, chloroform, iodoform, etc.,
   • Dyes, transparent soaps.
3. As a substitute for petrol under the name power alcohol used as fuel for aeroplane.
4. It is used as a preservative for biological specimens.

Question 15.
Mention the uses of Glycerol.
Answer:

1. Glycerol is used as a sweetening agent in confectionery and beverages.
2. It is used in the manufacture of cosmetics and transparent soaps.
3. It is used in making printing inks and stamp pad ink and lubricant for watches and clocks.
4. It is used in the manufacture of explosive like dynamite and cordite by mixing it with china clay.

Question 16.
Compare the acidity of 1°, 2° and 3° alcohols.
Answer:
1. The acidic nature of the alcohol is due to the polar nature of O – H bond. When an electron withdrawing -I groups such as – Cl, – F etc… is attached to the carbon bearing the OH group, it withdraws the electron density towards itself and thereby facilitating the proton donation.

2. In contrast, the electron releasing group such as alkyl group increases the electron density on oxygen and decreases the polar nature of 0 – H bond, I lence it results in the decrease in acidity.

3. On moving from primary to secondary and tertiary alcohols, the number of alkyl groups which attached to the carbon bearing -OH group increases, which results in the following order of acidity.
1°alcohol > 2° alcohol > 3° >alcohol

For example

Question 17.
What are dihydric phenols? Give three examples.
Answer:
When benzene ring has 2 – OH groups, it is called Dihydric phenol.

Question 18.
What are Trihydric phenols. Give example.
Answer:
When 3 – OH groups are present in benzene ring, it is called trihydric phenol.

Question 19.
Write the possible isomers for the formula C₇H₈O with their names C₇H₈O
Answer:
1. C₆H₅ – CH₂OH : Benzyl alcohol

2. C₆H₅ – O – CH₃ : Anisole

3.

4.

5.

Question 20.
Explain about the bromination of phenol.
Answer:
1. Phenol reacts with bromine water to give a white precipitate of 2, 4, 6 – tri bromo phenol.

2. When phenol reacts with Br₂ in the presence of CS₂ or CCl₄ at 278K. a mixture of ortho and para bromo phenols are formed.

Question 21.
Differentiate phenols from alcohol.
Answer:
Test to differentiate alcohols and phenols:
1. Phenol react with benzene diazonium chloride to form a red orange dye, but ethanol has no reaction with it.

2. Phenol gives purple colouration with neutral feme chloride solution, alcohols do not give such coloration with FeCI₃.

3. Phenol reacts with NaOH to give sodium phenoxide. Ethyl alcohol does not react with NaOH

Question 22.
What are the uses of phenol?
Answer:

1. About half of world production of phenol is used for making phenol formaldehyde resin. (Bakel ite).
2. Phenol is a starting material for the preparation of
   • drugs such as phenacetin, Salol, aspirin, etc.
   • phenolphthalein indicator.
   • explosive like picric acid.
3. It is used as an antiseptic – carbolic lotion and carbolic soaps.

Question 23.
Write the structure formula and IUPAC name of the following.

1. n – heptyl phenyl ether
2. Isopentyl phenyl ether
3. Dimethyl glycolate

Answer:

Question 24.
ExplaIn about the mechanism of intermolecular dehydration of ethanol with conc.H₂SO₄ at 413 K.
Answer:
When ethanol reacts with conc.H₂SO₄ at 413 K, inter molecular dehydration takes place and the product formed is Ethoxy ethane.
Mechanism:

Question 25.
Explain about the mechanism involved in Williamson’s synthesis.
Answer:
When an alkyl halide is heated with an alcoholic solution of sodium alkoxide, the corresponding ether is formed. This reaction involves SN² mechanism.

Mechanism:

Question 26.
Explain the mechanism involved in the reaction between Tertiary alkyl halide and primary alkoxide with eample.
Answer:
When tertiary alkyl halide reacts with primary alkoxide, elimination dominates and succeeds over substitution to form an alkene.

Question 27.
Explain about the reaction mechanism of methoxy ethane with HI.
Answer:
Ethers can undergo nucleophilic substitútion reactions with HI.

Ethers having primary alkyl group undergo SN² reaction whereas tertiary alkyl ether undergo SN¹ reaction. Protonation of ether is followed by the attack of halide ion. The halide ion preferentially attacks the less sterically hindered of the two alkyl groups which are attached etherial oxygen.

Question 28.
What are the uses of diethyl ether.
Answer:

1. Diethyl ether is used as a surgical anesthetic agent in surgery.
2. It is a good solvent for organic reactions and extraction.
3. It is used as a volatile starting fluid for diesel and gasoline engine.
4. It is used as a refrigerant.

Question 29.
Classify the following as primary secondary and tertiary alcohols.

Answer:
Primary alcohols:

Secondary alcohols:

Tertiary alcohols:

Question 30.
Name the following compounds according to IUPAC system.

Answer:

Question 31.
Show how are the following alcohols prepared by the reaction of a suitable Grignard reagent on methanal?

Answer:

Question 32.
You are given benzene, conc H₂SO₄ and NaOH. Write the equations for the preparation of phenol using these reagents.
Answer:

Question 33.
How will you convert ethanol to acetone ?
Answer:

Question 34.
How are the following conversions carried out?

1. Phenol to Toluene
2. Ethanol to 1, 1 – dichloroethane.

Answer:

Question 35.
How are the following conversions carried out ? (Write the reactions and conditions in each case):

1. Ethanol to 2 – propanol
2. Phenol to Acetophenone

Answer:

Samacheer Kalvi 12th Chemistry Hydroxy Compounds and Ethers 5 Mark Questions and Answers

II. Answer the following questions.

Question 1.
Explain Victor Meyer’s test used to distinguish 1°, 2° and 3° alcohols.
Answer:
Victor Meyer’s test :
This test is based on the behaviour of nitro alkanes formed by the three types of alcohols with nitrous acid and it consists of the following steps.

1. Alcohols are converted into alkyl iodide by treating with I₂/P.
2. Alkyl iodides so formed is then treated with AgNO₂ to form nitro alkane.
3. Nitro alkanes are finally treated with HNO₂ (mixture of NaNO₂/HCl) and the resultant solution is made alkaline with KOH.

Result:

1. Primary alcohol gives red colour
2. Secondary alcohol gives blue colour.
3. No colouration will be observed in tertiary alcohol.

1° alcohol:

2°alcohol:

3°alcohol:

Question 2.
Write the possible isomers for the formula C₄H₁₀O, write their IUPAC names and structures.
Answer:
C₄H₁₀O – 7 Isomers

Question 3.
Explain about mechanism involved in the dehydration of tertiary alcohols.
Answer:
Tertiary alcohols undergo dehydration by E₁ mechanism. It involves the formation of a carbocation.
Step 1:

Step 2:
Dissociation of oxonium ion to form a carbocation

Step 3:
Deprotonation of carbocation to form an alkene

Question 4.
Explain about the various dehydration reactions of ethylene glycol.
Answer:
Ethylene glycol undergoes dehydration reaction under different conditions to form different products.
1. When ethylene glycol is heated to 773K, it forms epoxides.

2. When heated with dilute sulphuric acid (or) anhydrous ZnCl₂ under pressure in a sealed tube, it gives acetaldehyde.

3. When distilled with Conc. H₂SO₄, glycol forms 1, 4 – dioxane

Question 5.
Explain the following reactions.

1. Schotten-Baumann reaction
2. Kolbe’s reaction
3. Reimer – Tiemann reaction

Answer:
1. Schotten – Baumann reaction:

2. Kolbe’s reaction:

3. Reimer – Tiemann reaction.

Question 6.
Describe the following electrophilic substitution reaction using phenol.

1. Nitrosation
2. Nitration
3. Sulphonation

Answer:
1. Nitrosation:
Phenol can be readily nitrosoated at low temperature with nitrous acid.

2. Nitration:
Phenol can be nitrated using 20% nitric acid at room temperature, a mixture of ortho and para nitro phenols are formed.

3. Phenol when treated with Conc.HNO₃ and Conc.H₂SO₄, picric acid is formed.

4. Sulphonation:
Phenol when reacts with Conc.H₂SO₄ at 280K, o – phenol suiphonic acid is formed as major product. But when the reaction is carried out at 313K, the major product is p – phenol suiphonic acid.

Question 7.
What happens when diethyl ether reacts with following reagents.

1. excess O₂
2. Cl₂ / light
3. PCI₅
4. dil.H₂SO₄ / H₂O
5. CH₂COCI /Anhydrous ZnCI₂.

Answer:
Auto – oxidation:

Question 8.
Explain the aromatic electrophilic substitution reactions of anisole with equations. Aromatic electrophilic substitution reactions:
Answer:
1. Halogenation:

2. Nitration.

3. Friedel Craft’s alkylation.

4. Friedel Craft’s acylation.

Question 9.
Starting from phenol, how would you prepare the following compounds.

1. Benzene
2. Aniline
3. Anisole
4. 1, 4, benzoqulnone
5. Cyclohexanol

Answer:

Question 10.
A compound ‘A’ with molecular formula C₄H₁₀O is unreactive towards sodium metal. it does not add Bromine water and does not react with NaHSO₃ solution. On refluxing ‘A’ with excess of HI, it gives ‘B’ which reacts with aqueous NaOH to form ‘C’. ‘C’ can be converted into ‘B’ by reacting with red P and I₃. ‘C, on treating with conc. H₂SO₄ forms ‘D’. ‘D’ decolounses bromine water. Identify A to D and write the reactions involved.
Answer:

‘A’ is not an alcohol therefore it does not react with sodium metal. ‘A’ is also not an aldehyde or a ketone as it does not react with NaHSO3. ‘A’ is not an unsaturated hydrocarbon as it does not add Br₂ (aq). So, it is likely to be a ether.

Question 11.
An organic compound (A) of molecular formula C₂H₆O on reaction with conc.H₂SO₄ at 443 K gives an unsaturated hydrocarbon (B). (B) on reaction with Baeyer’s reagent produces (C) of molecular formula C₂H₆O₂. (C) on reaction with anhydrous ZnCI₂ produces (D) of molecular formula C₂H₄O. (D) reduces Tollen’s reagent. Identify A, B, C and D and explain the reactions involved.
Answer:
1. An organic compound (A) reacts with Conc.H₂SO₄ at 443 K produces ethene by intermolecular dehydration. So, (A) is ethanol – CH₃CH₂OH.

2. Ethene on reaction with Baeyer’s reagent (cold, dilute alkaline KMnO₄) produces ethylene glycol as product (C).

3. Ethylene glycol on reaction with anhydrous ZnCI₂ dehydration and tautomerisation take place to give actaldehyde as product (D).

Question 12.
An organic compound (A) of molecular formula C₂H₆O liberates H₂ gas with metallic sodium and gives (B). (B) on reaction with methyl bromide produces (C) of molecular formula C₃H₈O. (C) on reaction with excess III produces (D) and (E). Identify A, B, C, D and E and explain the reactions involved.
Answer:
1. An organic compound (A) reacts with Na metal and liberates H₂ gas means it must be an alcohol. From the molecular formula it is identified as ethanol – CH₃ – CH₂OH (A).

2. Ethanol on reaction with Na metal to produce sodium ethoxide as (B) with liberation of H₂ gas.

3. Sodium ethoxide on reaction methyl bromide undergo Williamson’s synthesis to produce methoxy ethane as (C).

4. Methoxy ethane on reaction with excess HI will give Ethyl iodide and Methyl iodide as (D) and (E).

Question 13.
An organic compound (A) of molecular formula CH₄O on mild oxidation gives (B) of formula CH₂O that reduces tollen’s reagent. (B) on reaction with methyl magnesium bromide followed by acid hydrolysis will give (C) of molecular formula C₂H₆O which liberates H₂ gas with metallic sodium. Identify A, B, C and explain the reactions involved.
Answer:
1. (A) is identified from the molecular formula as methanol (CH₃OH).

2. CH₃OH – methanol on mild oxidation will give formaldehyde as (B). Aldehydes reduce Tollen’s reagent to silver mirror. So, (B) is HCHO (methanal)

3. Formaldehyde reacts with CH₃MgBr, followed by acid hydrolysis produces primary alcohol and (C) is identified from the formula as CH₃ – CH₂OH – Ethanol. Ethanol liberates H₂ gas with metallic sodium.

Question 14.
An organic compound (A) of molecular formula C₂H₆O reacts with metallic Na and liberates H₂ gas. (A) on mild oxidation with Cu at 573 K gives (B) of molecular formula C₂H₄O. (B) on reaction with methyl magnesium bromide followed by acid hydrolysis gives (C) of molecular formula C₃H₅O. (C) gives Blue colour in Victor Meyer’s test. (C) on mild oxidation with Cu at 573 K gives (D) of formula C₃H₆O. identify A, B, C, D and
explain the reactions.
Answer:
1. An organic compound (A) reacts with Na metal and liberates H₂ gas means it must be alcohol. From the molecular formula it is identified as Ethanol (CH₃ – CH₂OH).

2. Ethanol on oxidation with Cu at 573 K undergoes catalytic dehydrogenation and produces Acetaldehyde as product (B).

3. Acetaldehyde on reaction with CH₃MgBr followed by hydrolysis will give Isopropyl alcohol as (C).

4. Propan – 2 – ol is secondary alcohol and so it gives blue colour in Victor Meyer’s test. (C) on reaction with Cu at 573 K will give Propanone as (D).

Question 15.
An organic compound (A) of molecular formula C₃H₈O gives blue colour in Victor Meyer’s test. (A) on reaction with Cu at 573 K gives (B) which further reacts with Methyl magnesium bromide followed by acid hydrolysis yields (C) of molecular formula C₄H₁₀O. (C) on reaction with Cu at 573 K gives (D) of formula C4H8. Identify A, B, C, D and explain the reactions involved.
Answer:
1. An organic compound gives blue colour in Victor Meyer’s test means it must be a secondary alcohol. From the formula, it is identified as
Propan – 2- ol (A)

2. Propan – 2 – ol on reaction with Cu at 573 K gives Propanone as (B).

3. Propanone on treatment with CH₃MgBr followed by acid hydrolysis will yield Tertiary butyl alcohol (CH₃)₃C – OH as (C).

4. Tertiary butyl alcohol on reaction with copper at 573 K undergoes dehydration reaction to

Question 16.
An organic compound (A) of molecular formula C₃H₆ on reaction with Conc. H₂SO₄ and H₂O gives ClH₅O as (B) as a MarkownikoWs product. (B) on oxidation with Cu at 573 K gives (C) of formula C₃H₆O. (C) on reaction with CH₃MgBr followed by acid hydrolysis yields (D) as C₄H₁₀O which will not give any colour in Victor Meyer’s test. Identify A, B, C, D and explain the reactions involved.
Answer:
1. An organic compound (A) is identified from the molecular formula as CH₃ – CH = CH₂ propene.

2. Propene on hydrolysis in acid medium, Markownikoff’s rule is followed and the product formed is
Propan – 2- ol as (B)

3. Propan – 2 – ol on reaction with Cu at 573 K undergoes dehydrogenation reaction to produce Propanone as (C).

4. Propanone on reaction with CH₃MgBr followed by acid hydrolysis gives tertiary butyl alcohol (D). It will not give any colouration in Victor Meyer’s test.

Question 17.
An aromatic compound (A) of molecular formula C₆H₅Cl on reaction with aqueous NaOH gives (B) of formula C6H60 that give violet colouration with neutral FeCI₃. (B) on reaction with ammonia in presence of anhydrous ZnCI₂ gives (C) of formula C₆H₇N. Identify A, B, C and explain the reactions.
Answer:
1. An aromatic compound (A) of molecular formula C₆H₅Cl is identified as chioro benzene.

2. Chioro benzene on reaction with aqueous NaOH produces phenol as (B).

3. Phenol gives violet colour with neutral FeCI₃. Phenol on treated with NH₃ in the presence of anhydrous ZnCl₂ gives Aniline as (C).

Question 18.
An organic compound (A) of molecular formula C₆H₆O gives white precipitate with bromine water. (A) on reaction with NaOH gives (B). (B) reacts with methyl iodide in presence of dry ether gives (C) of molecular formula C₇H₈O which will not liberate H₂ gas with metallic Na. (C) on reaction with acetvl chloride gives (D) and (E) of formula which are position isomers. Identify A, B, C, D & E and explain the reaction.
Answer:
1. An organic compound gives white precipitate with bromine water means it must be a phenol. From the molecular formula it is identified as C₆H₅OH.

2. Phenol on reaction with NaOH gives (B) as sodium phenoxide C₆H₅ONa.

3. Sodium phenoxide on reaction with methyl iodide in the pressure of dry ether undergo Williamsons synthesis and gives Anisole as (C).

4. Anisole on reaction with acetyl chloride undergoes Fnedel Craft’s acetylation and yield O – methoxy acetophenone and p-methoxy acetophenone as (D) and (E).

Question 19.
An organic compound (A) of molecular formula C₆H₅CI on reaction with aqueous NaOH gives (B) of formula C₆H₆O. (B) on reaction with NaOH gives (C) of formula C₆H₅ONa. (C) on treatment with CO₂, followed by acid hydrolysis yield (D) of formula C₇H₆O₃ an aromatic hydroxy acid. Identify A, B, C, D and explain the reactions involved.
Answer:

1. (A) is identified from the formula as C₆H₅CI – Chloro benzene.
2. Chloro benzene on treatment with aqueous NaOH yeilds C₆H₅OH – phenol as (B).
3. Phenol on reaction with NaOH produces sodium phenoxide C₆H₅ONa as (C).
4. Sodium phenoxide on reaction with CO₂, followed acid hydrolysis, Kolbe’s reaction takes place to give Salicylic acid as (D).

Question 20.
An organic compound (A) of molecular formula C₆HN₂Cl on boiling with hot water gives (B) of molecular formula C₆H₆O. (B) on reaction with Zinc dust gives (C) a simplest aromatic hydrocarbon. (C) on reaction with methyl chloride in the presence of anhydrous AICI₂ gives (D) of molecular formula C₇H₈. Identify A, B, C, D and explain the reaction.
Answer:
1. (A) is identified from the formula as Benzene diazonium chloride – C₆H₅N₂Cl.

2. Benzene diazonium chloride when boiled with hot water produces phenol as (B).

3. Phenol on reaction with Zinc dust gives Benzene as (C) which is simplest aromatic hydrocarbon.

4. Benzene on treatment with (C) methyl chloride in the presence of anhydrous AlCl₃, Friedel Crafts reaction take place and the product formed is Toluene as (D).

Question 21.
An organic compound (A) of molecular formula C₆H₆O gives violet colour with neutral FeCI₃. (A) reacts benzene diazoniurn chloride in basic medium to give (B) as an azo dye. (A) reacts with acidified K₂Cr₂O₇ gives (C) of formula C₆H₄O₂. (A) on reaction with H₂ in the presence of nickel gives (D) of formula C₆H₁₂O. Identify A, B, C, D and explain the reaction involved.
Answer:
1. (A) of molecular formula C₆H₆O gives violet colour with neutral FeCI₃ means it must be Phenol – C₆H₅OH.

2. Phenol couples with benzene diazonium chloride in the presence of basic medium to produce p-hydroxy azo benzene, a red orange dye as (B).

3. Phenol on reaction with acidified K₂Cr₂O₇ undergoes oxidation reaction to give 1, 4 – benzo quinone as (C).

4. Phenol on reaction with H₂, in the presence of Nickel gives cyclohexanol as (D).

Question 22.
An organic compound (A) of molecular formula C₆H₆ reacts with propylene in the presence of H₃PO₄ at 532 K gives (B) of formula C₉H₁₂ . (B)on air oxidation gives C₉H₁₂O₂ as (C). (C) on acidification with H₂SO₄ gives (D) of formula C₆H₆O and (E) of formula C₃H₆O. Identify A, B, C, D and E and explain the reactions.
Answer:
1. (A) is identified as benzene from the molecular formula.

2. Benzene reacts with propylene in the presence of H₃PO₄ gives cumene as (B).

3. Cumene on air oxidation produces cumene hydroperoxide as (C).

4. Cumene hydroperoxide on treatement with H₂SO₄ yield phenol as (D) and acetone as (E).

Question 23.
An organic compound (A) of molecular formula C₂H₆O reacts P/I₂ gives (B) which on further reaction with silver nitrite gives (C) of formula C₂H₅NO₂. (C) on treatment with nitrous acid yield (D) of formula C₂H₄N₂O₃. (D) on reaction with KOH give red color product (E). Identify A, B, C, D and E. From the final product (E) red colour product, it is identified these reactions are the reactions of primary alcohols in Victor Meyer’s test.
Answer:

Question 24.
An organic compound (A) of molecular formula C₃HO on reaction P/I₂ gives C₃H₇I as (B). (B) on reaction with AgNO₂ produces (C) with formula C₃H₇NO₂. (C) on reaction with nitrous acid gives (D) of molecular formula C₃H₆N₂O₃. (D) on reaction with KOH produces blue colour. Identify A, B. C, D and explain the reaction.
Answer:
From the final colour blue, this reaction are considered as reactions of secondary alcohol in Victory Meyer’s. (A) is identified as  2 – propanol.

Question 25.
An organic compound (A) of molecular formula C₄H₁₀O gives no colouration in Victor Meyer’s test. (A) on reaction with P / I₂ gives (B) of formula C₄H₉I. (B) on treatment with nitrous acid gives (C) of formula C₃H₉NO₂. (C) does not react with KOH. Identify A, B, C and explain.
Answer:
C₄H₁₀O gives no colouration in Victor Meyer’s test means it must be tertiary alcohol. So (A) is tertiary butyl alcohol. The reactions involved are,

Common Errors

1. Writing IUPAC names may be difficult and students may get confused.
2. Primary, Secondary and Tertiary alcohols functional groups may get confused. Phenol, aromatic alcohols are differenet.
3. Benzene ring should be drawn properly.
4. Skeleton carbon chain may be a problem to students.

Rectifications

1. Parent hydrocarbon – longest carbon chain. Lowest number of the carbon having functional group. Arrangement of substitutents in alphabetical order. Alcohol – Name should end in the word ol.

2. Primary alcohol – CHI₂OH, Secondary alcohol > CHOH, Tertiary alcohol > COH – OH gp/ directly attached to benzene ring is
Phenol
It is not aromatic alcohol
– OH gp/ is attached to the side chain of the benzene ring is an aromatic alcohol.

Benzyl alcohol

3. Altemat double bond along with regular hexagon is ben zeane.
Benzene (C₆H₆) If you draw the above structure without double bonds, it is cyclo hexane.
Cyclohexane (C₆H₁₂)

4.
CH₃ – CH₂ – CH₂ – CH₂ – CH₂ – CH₂ – CH₃
n-heptane

CH₃ – CH₂ – CH₂ – CH = CH₂
Pent – 1 – ene

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Tamilnadu Samacheer Kalvi 8th Social Science Civics Solutions Term 2 Chapter 2 Human Rights and UNO

Samacheer Kalvi 8th Social Science Civics Human Rights and UNO Textbook Evaluation

I. Choose the correct answer

Human Rights And Uno 8th Standard Question 1.
After the Second World War ……………. has taken several measures to protect the human rights.
(a) UNO
(b) Supreme Court
(c) International Court of Justice
(d) None
Answer:
(a) UNO

Human Rights And Uno 8th Standard Samacheer Kalvi Question 2.
In 1995 women from all over the world gathered at ……………..
(a) Beijing
(b) New York
(c) Delhi
(d) None
Answer:
(a) Beijing

Human Rights Lesson Class 8 Question 3.
The National Human Rights Commission was constituted in ………………
(a) 1990
(b) 1993
(c) 1978
(d) 1979
Answer:
(b) 1993

Human Rights Class 8th Question 4.
The UNO declared 1979 as the International year of ……………..
(a) Girl Child
(b) Children
(c) Women
(d) None
Answer:
(c) Women

Human Rights 8th Standard Notes Question 5.
When is Human Rights Day observed?
(a) 9th December
(b) 10th December
(c) 11th December
(d) 12th December
Answer:
(b) 10th December

8th Standard Social Human Rights Notes Question 6.
Which one is known as modern International Magna Carta of Human rights?
(a) UDHRC
(b) NHRC
(c) SHRC
(d) International year for women
Answer:
(a) UDHRC

Human Rights 8th Standard Question 7.
Who can be appointed as the chairperson of the National Human Rights Commission?
(a) Retired judge of high court
(b) Any retired Chief Justice of the Supreme Court.
(c) Any person appointed by the president.
(d) Retired Chief Judge of any court.
Answer:
(c) Any person appointed by the president.

Human Rights 8th Std Notes Question 8.
How many articles does the Universal Declaration of Human Rights contain?
(a) 20
(b) 30
(c) 40
(d) 50
Answer:
(b) 30

Human Rights And Uno Question 9.
What is the tenure of the Chairperson of the National Human Rights Commission?
(a) 5 years or upto 62 years of age
(b) 5 years or upto 65 years of age
(c) 6 years or upto 65 years of age
(d) 5 years or upto 70 years of age
Answer:
(d) 5 years or upto 70 years of age

Question 10.
Where is the headquarters of the National Human Rights Commission?
(a) Delhi
(b) Mumbai
(c) Ahmedabad
(d) Kolkata
Answer:
(a) Delhi

II. Fill in the Blanks

1. Each individual has ………….. to lead a dignified life.
2. Human Rights are ………….. rights.
3. The State Human Rights commission was formed on ……………
4. Article 24 of Indian Constitution prohibits ……………
5. United Nations Organisation was established in the year ……………

Answer:

1. Right
2. Fundamental rights
3. 17th April 1997
4. Child Labor
5. 24th October 1945

III. Match the following:

1. Eleanor Roosevelt – world’s first charter of human rights
2. The Cyrus Cylinder – 1997
3. Eve Teasing Act – freedom from slavery
4. Child help line – Human Rights Commission
5. Civil right – right to vote
6. Political right – 1098

Answer:

1. Eleanor Roosevelt – Human Rights Commission
2. The Cyrus Cylinder – world’s first charter of human rights
3. Eve Teasing Act – 1997
4. Child help line – 1098
5. Civil right – freedom from slavery
6. Political right – right to vote

IV. State True or False

1. Human rights and civil rights are the same.
2. Declaration of the Rights of Man and of the Citizen was proclaimed in India.
3. The Human Right Act of 1993 provides the creation of National Human Rights Commission.
4. National Human Rights Commission has empowered to give punishment to the victims.
5. ………….. was empowered to setup commission for the promotion of Human rights at National and State level.

Answer:

1. True
2. True
3. False
4. True
5. ECOSOC

V. Consider the following statements and tick the appropriate answer

Question 1.
Find the wrong statement
(a) National Human Rights Commission is a statutory body.
(b) National Human Rights Commission is a constitutional body.
(c) National Human Rights Commission is an independent body.
(d) National Human Rights Commission is a multilateral institution.
Answer:
(b) National Human Rights Commission is a constitutional body.

Question 2.
Which of the following statement is not correct about the National Human Rights Commission?
(a) It was established in 1993.
(b) In the cases of human rights violation, the Commission has no rights to punish the culprit.
(c) The Chairperson and members are of this Commission are appointed by the Supreme Court of India.
(d) The Commission sends its annual report to the Central Government and State Governments.
Answer:
(c) The Chairperson and members are of this Commission are appointed by the Supreme Court of India.

Question 3.
Assertion (A) : Human Rights day is observed on 10th December
Reason (R) : It commemorates Eleanor Roosevelt’s birthday.
(a) A is correct but R does not explain A
(b) A is correct but R explains A
(c) A and R are correct
(d) A and R are Wrong
Answer:
(a) A is correct but R does not explain A

Question 4.
Consider the following statements

1. The State Human Rights Commission is a multi-member body.
2. The State Human Rights Commission consists of a chairperson and three members.

Which of the statements given above is /are correct?
(a) 1 only
(b) 2 only
(c) Both a and b
(d) None
Answer:
(a) 1 only

VI. Answer the following in one or two sentences

Question 1.
What are Human Rights?
Answer:

1. Human rights are rights inherent to all human beings regardless of race, sex, nationality, ethnicity, language and religion.
2. Human rights include freedom from slavery and torture, freedom of opinion and expression and fair trial. The right to life work and education.

Question 2.
Bring out the importance of UDHR.
Answer:

1. One of the greatest achievements of United Nations is the creation of human rights law.
2. To advance this goal, the UN established a Commission of Human Rights.
3. it is also known as modem International Magna Carta of Human Rights.
4. It is the most translated document in the world.

Question 3.
What does Article 45 of Indian Constitution provide?
Answer:
Article 45 of Indian Constitution provides that the state shall endeavor to provide early childhood care and education for all children until they complete the age of six years.

Question 4.
Write about Right to Education Act.
Answer:
Article 21A provides that the state shall provide free and compulsory education to all children aged six to fourteen years.

Question 5.
State any three legislation passed to safeguard the welfare of women.
Answer:

1. The Hindu Widow Remarriage Act 1856
2. The Hindu Marriage Act 1955.
3. The Hindu Succession Act 1956.

Question 6.
Mention some of the political rights.
Answer:
The freedom of expression, and peaceful assembly, the right to take part in the government of one’s country, the right to vote, the freedom of speech and obtain information.

Question 7.
Name the five primary categories of Human Rights.
Answer:

1. Civil Rights
2. Political Rights
3. Social Rights
4. Economic Rights
5. Cultural Rights

VII. Answer the following in detail:

Question 1.
Distinguish between Human rights and Civil rights.
Answer:
Human Rights:

1. Human Rights belong to everyone, everywhere, regardless of nationality, sexuality, gender, race, religion or age.
2. Human rights are considered universal to all human beings and universsal in all countries.
3. No nation may rightfully deprive human rights to an individual.
4. Human rights are basic rights inherent with birth.

Civil Rights:

1. Civil rights are those rights that one enjoys by virtue of citizenship in a particular nation or state.
2. Civil rights vary greatly from country to the country’s or government to government. It is related to the constitution.
3. Different nations can grant or deny different civil rights and liberties.
4. Civil rights are creation of the society.

Question 2.
Describe any five basic characteristics of Human rights.
Answer:

1. Inherent – they are not granted by any person or authority.
2. Fund ntal – they are fundamental rights because without them, the life and dignity of man will be meaningless.
3. Inalienable – they cannot be taken away from the individual.
4. Indivisible – they can’t be denied even when other rights have already been enjoyed.
5. Universal – they are universal. They apply irrespective of one’s origin or status. They are enforceable without national border.

Question 3.
What are the measures taken by the government to protect the children?
Answer:

1. The child is considered as an important national asset.
2. The future of a nation depends on how its children mature and develop.
3. So protection of children from all kinds of exploitation and abuses has become the main objective of our society.
4. There are laws in India protecting the rights of the children.

(a) Right to Education Act:
Article 21A provides that the state shall provide free and compulsory education to all children aged six to fourteen years.

(b) The Child Labour Act (Prohibition and Regulation Act 1986):
It provides no child who has not completed 15 years of age can be employed.

(c) The Juvenile Justice Act 2000 (Care and Protection of Children):
This Act tries to protect children deprived of adequate care and to reform the children by adopting child friendly approach.

(d) POCSO A I 2012:
Protection of children from Sexual Offences Act regards the best interest of the child as being paramount importance in’every state.

VIII. HOTs

Question 1.
To whom does the Universal Declaration of Human Rights apply? Why is it important to you?
Answer:
To each individual, regardless of gender, race, religion or cultural background. Because it protects and promotes your individual rights.

IX Project and Activity

Question 1.
Make a list of 10 rights that you enjoy, and the responsibilities that you have.
Answer:
Rights :

1. Right to life
2. Right to family life
3. Right to education
4. Right to personal freedom
5. Right to religious freedom
6. Right to freedom of movement
7. Freedom of press
8. Right to equality
9. Right to justice
10. Freedom to form associations

Responsibilities:

1. Support and defend the constitution
2. Stay informed of the issues affecting your community.
3. Participate in the democratic process.
4. Respect and obey federal, state and local laws.
5. Respect the rights, beliefs, and opinion of others.
6. Participate in your local community.
7. Serve on a jury when called upon.
8. Defend the country if the need should arise.
9. Pay income and other taxes honestly and on time, to federal, state and local authorities.

Samacheer Kalvi 8th Social Science Civics Human Rights and UNO Additional Questions

I. Choose the correct answer:

Question 1.
After the ……………. war, UNO has taken several measures to protect the human rights.
(a) First world
(b) Second world
(c) Third world
(d) None of these
Answer:
(b) Second world

Question 2.
In ………….. women from all over the world gathered at Beijing.
(a) 1994
(b) 1995
(c) 1999
(d) 1996
Answer:
(b) 1995

Question 3.
The ………….. commission was constituted in 1993.
(a) State Human Rights
(b) Local Human Rights
(c) National Human Rights
(d) Union Human Rights
Answer:
(c) National Human Rights

Question 4.
The ………….. declared 1979 as the International year of women.
(a) UNO
(b) UNESCO
(c) UDHRC
(d) SHRC
Answer:
(a) UNO

Question 5.
………….. is celeberated on 10th December every year.
(a) Valentine’s day
(b) Human Freedom Day
(c) Human Rights Day
(d) World Environment Day
Answer:
(c) Human Rights Day

Question 6.
………….. of Human Rights contain 30 Articles.
(a) Universal Declaration
(b) National Declaration
(c) State Declaration
(d) District Declaration
Answer:
(a) Universal Declaration

Question 7.
The ………….. was formed on 17th April 1997.
(a) Universal Human Rights Commission
(b) State Human Rights Commission
(c) District Human Rights Commission
(d) Local Human Rights Commission
Answer:
(b) State Human Rights Commission

Question 8.
………….. was established in the year 1945.
(a) UNESCO
(b) SHRC
(c) NHRC
(d) UNO
Answer:
(d) UNO

Question 9.
………….. are related to individuals and society.
(a) Human Liberty
(b) Human Rights
(c) Human Freedom
(d) Petition of Right
Answer:
(b) Human Rights

Question 10.
One of the greatest achievements of ………….. is the creation of Human Rights Law.
(a) India
(b) United Kingdom
(c) United Nation
(d) All the above
Answer:
(c) United Nation

Question 11.
Expand form of UDHR …………..
(a) United Declaration of Human Rights
(b) Universal Declaration of Human Rights
(c) Universal Development of Health Rights
(d) Universal Declaration of Health Rights
Answer:
(b) Universal Declaration of Human Rights

Question 12.
UDHR was adopted by the UN General Assemly in ……………
(a) 1948
(b) 1949
(c) 1950
(d) 1947
Answer:
(a) 1948

Question 13.
………….. refers to the basic rights afforded by law of the government to every person.
(a) Human Rights
(b) Freedom Rights
(c) Civil Rights
(d) Fundamental Rights
Answer:
(c) Civil Rights

Question 14.
………….. are exercised in the formation and administration of a government.
(a) Civil rights
(b) Political rights
(c) Social rights
(d) Economic rights
Answer:
(b) Political rights

Question 15.
The civil and Political rights are directly related to ………….. democracy.
(a) modem
(b) classical
(c) tradition
(d) all the above
Answer:
(a) modern

Question 16.
………….. rights are those rights necessary for an adequate standard of living ncluding the rights in education and health etc.
(a) Economic
(b) Civil
(c) Political
(d) Social
Answer:
(d) Social

Question 17.
The convention on the rights of the Rights of the child was proclaimed by UN on …………..
(a) 20th November 1989
(b) 20th December 1989
(c) 20th October 1989
(d) 20th September 1989
Answer:
(a) 20th November 1989

Question 18.
………….. provides no child who has not completed 15 years of age can be employed.
(a) POCSO Act
(b) Right to Education Act
(c) The Child Labour Act
(d) The Juvenile Justice Act
Answer:
(c) The Child Labour Act

Question 19.
UNO has declared ………….. as International.year of women.
(a) 1979
(b) 1978
(c) 1980
(d) 1961
Answer:
(b) 1978

Question 20.
………….. has declared 1979 as the International year of children.
(a) POCSO
(b) UDHRC
(c) UNO
(d) NHRC
Answer:
(c) UNO

II. Fill in the blanks:

1. ………….. are basic rights inherent with birth.
2. A ………….. means every human being below the age of 18 years.
3. ………….. was adopted by UN General Assembly in 1948.
4. In 1995 the …………… world conference of women, held in Beijing.
5. Indian Constitution Article 39 (F) provides for …………… to develop in healthy manner.
6. ………….. rights includes the rights to life, liberty, freedom from slavery and arbitrary arrest.
7. The United Nations Organisation was drafted in …………….
8. A set of basic right and freedom has deep roots in ……………. and ……………. countries.
9. There are 30 Articles incorporated in the ……………..
10. …………….. the great, the first king of Ancient Persia.
11. UNO was established on …………….. 1945.
12. …………….. during the Second World War made clear that previous efforts to protect body.
13. Expand form of ECOSOC ……………
14. NHRC is an …………… and …………… body.
15. NHRC is Multi member body which consists of a …………… and other members.
16. NHRC has ……………… division.
17. The State Human Rights Commission of ………….. was formed on 17th April 1997.
18. State Human Rights Commission consists of ……………. members including Chairperson.
19. The headquarter of NHRC is located at …………….

Answer:

1. Human Rights
2. Child
3. UDHR
4. fourth
5. Children
6. Civil
7. 1945
8. European and American
9. Universal Declaration of Human Rights
10. Cyrus
11. 24th October
12. rocities
13. The Economic and Social Council
14. Independent statutory and non-constitutional
15. Chairperson
16. Five
17. Tamil Nadu
18. three
19. New Delhi

III. Match the following:

Answer:

1. e
2. c
3. a
4. b
5. d

Answer:

1. b
2. a
3. e
4. c
5. d

IV. State True or False

1. Every year 18th November is observed as the Human Rights Day.
2. The Headquarters of National Human Rights Commission is situated in Mumbai.
3. The Universal Declaration of Human Rights (UDHR) was adopted by the UN General Assembly in 1948.
4. Human Rights are related to individual and society.
5. There are 45 Articles incorporated in the Universal Declaration of Human Rights.
6. Indian Constitution Article 39(f) provides for Children to develop in healthy manner.
7. 1098 Child Line is India’s First 24 hours free emergency phone service for children in need if assistance.
8. The National Human Rights Commission’s Chairperson and other members appointed for 6 years.
9. The child is considered as an important national asset.
10. UNO has declared 1979 as the international year of women.
11. UNO has declared 1978 as international year of women.

Answer:

1. False
2. False
3. True
4. True
5. False
6. True
7. True
8. False
9. True
10. False
11. True

V. Consider the following statements and Tick (✓) the appropriate answer

Question 1.
Find the Correct Statement:
(i) Human Rights are inherent, inalienable, interdependent and indivisible.
(ii) In 1996 the fourth world conference of women, held in Beijing.
(iii) The Dowry Prohibition Act 1961.
(iv) The UNO has declared 1979 as the International Year of Children.

(a) (i), (ii) & (iii) are Correct
(b) (i), (ii) & (iv) are Correct
(c) (i), (iii) and (iv) are Correct
(d) (ii), (iii) and (iv) are Correct
Answer:
(c) (i), (iii) and (iv) are Correct

Question 2.
Assertion (A) : Indian Constitution Article 39(f) provides for Children to develop in healthy manner.
Reason (R) : The child is considered as an important national assets.
(a) A is correct and R is the correct explanation of A
(b) A is correct but R is wrong
(c) A is correct but R is not the correct explanation of A
(d) A is incorrect but R is correct
Answer:
(a) A is correct and R is the correct explanation of A

Question 3.
Which of the following is correctly matched?
(a) The Eve Teasing Act – 1998
(b) The Hindu Succession Act – 1956
(c) The Hindu Re – Marriage Act – 1958
(d) The Hindu Marriage Act – 1856
Answer:
(b) The Hindu Succession Act – 1956

Question 4.
Which of the following is not correctly matched?
(a) The Dowry Prohibition Act – 1961
(b) The Hindu Marriage Act – 1955
(c) Indecent Representation Act – 1998
(d) Protection of Women from Domestic Violence Act – 2005
Answer:
(c) Indecent Representation Act – 1998

VI. Answer in one or two sentences:

Question 1.
List out the Four basic characteristics of Human Rights.
Answer:

1. Inherent
2. Fundamental
3. Indivisible
4. Universal

Question 2.
What do you meant by human rights?
Answer:
Human rights belong to everyone, everywhere, regardless of nationality, sexuality, gender, race, religion or age.

Question 3.
What are Civil Rights?
Answer:
Civil Rights are those rights that one enjoys by virtue of citizenship in a particular nation or state.

Question 4.
Write a short note on National Human Rights Commission.
Answer:

1. The National Human Rights Commission (NHRC) of India was established on 12th October, 1993.
2. It is an independent statutory and non – constitutional body.
3. Its headquarter is located in New Delhi.

Question 5.
Who are them members of National Human Rights Commission (NHRC)?
Answer:
NHRC is a multi member body which consists of a Chairperson and other members. They are –

1. Chairperson (Retired) Chief Justice of India, Judge of Supreme Court, Judge of High Court, 2 members having practical knowledge relating to Human Rights and Deemed members.
2. Chairpersons of National Commission for Minorities, Scheduled Castes, Scheduled Tribes and Women.

Question 6.
Write a few lines about the State Human Rights Commission of Tamil Nadu.
Answer:

1. The State Human Rights of Tamil Nadu was formed on 17th April, 1997.
2. It function at the state level.
3. It consists of three members including a chairperson.

Question 7.
Expand POCSO and NHRC.
Answer:

1. POCSO : Protection of Children from Sexual Offences Act.
2. NHRC : National Human Rights Commission

Question 8.
Define Child Rights.
Answer:
According to Article 1 of the United Nations Convention on the Rights of the Child 1989, ‘a child means every human being below the age of eighteen years’.

VII. Answer the following in detail:

Question 1.
Explain the various kinds of Human Rights.
Answer:
These rights are broadly classified into five primary categories. They are as follows:

1. Civil Rights:
The term civil rights refers to the basic rights afforded by laws of the government to every person.

2. Political Rights:

• Political rights are exercised in the formation and administration of a government.
• The civil and political rights are directly related to modem democracy.
• It includes the freedom of expression and peaceful assembly, the right to take part in the government of one’s country, the right to vote, the freedom of speech and obtain information.

3. Social Rights:

• It is necessary for an individual to fully participate in the society.
• Social rights are those rights necessary for an adequate standard of living including the right to education, health care, food, clothing, shelter and social security.

4. Economic Rights:

• The right to participate in an economy that benefits all and to desirable work.
• Economic rights guarantee every person to have condition under which they are able to meed their needs.
• This includes the rights to employment and fair wage, the reasonable limitation of working hours etc.

5. Cultural Rights:
The rights to freedom of religion and to speak the language and to practice the cultural life of the community, the right to share in scientific advancement, and right to the protection of moral and material interest.

Question 2.
Discuss about the Universal Declaration of Human Rights (UDHR)
Answer:

1. One of the greatest achievements of United Nations is the creation of human rights law.

2. To advance this goal, the UN established a Commission on Human Rights.

3. The Commission guided by Eleanor Roosevelt’s (Wife of former US President Franklin D Roosevelt) forceful leadership captured the world’s attention.

4. The Universal Declaration of Human Rights (UDHR) was adopted by the UN General Assembly in 1948.

5. It is a milestone document in the history of Human rights.

6. The Declaration was proclaimed by the UN General Assembly in Paris, France on 10th December 1948 (General Assembly Resolution 217A).

7. In remembrance of every year 10th December is observed as the Human rights Day and its regular observance commenced from 1950.

8. It is also known as modem International Magna Carta of Human Rights.

9. Its principles have been incorporated into the Constitutions of most of the (more than 185) nations.

10. DHR has been translated into more than 500 languages.

11. It is the most translated document in the world.

You can Download Little Cyclone: The Story of a Grizzly Cub Questions and Answers, Summary, Activity, Notes, Samacheer Kalvi 9th English Book Solutions Guide Pdf Supplementary Chapter 5 help you to revise complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 9th English Solutions Supplementary Chapter 5 Little Cyclone: The Story of a Grizzly Cub

Little Cyclone: The Story of a Grizzly Cub Warm Up: 

Little Cyclone The Story Of A Grizzly Cub Question 1.
Why are some animals endangered?
Answer:
An animal is called endangered when only a few of its kind are alive in the world. There are many reasons for a species to become endangered. The environmental conditions on Earth are continually changing. Some animals become endangered because they can no longer survive in the new conditions of their changing habitat. Some other prominent reasons are overhunting by humans and pollution.

Little Cyclone The Story Of A Grizzly Cub Summary Question 2.
Why do wild animals from the forest often enter the human living spaces?
Answer:
Due to urbanisation, people are felling trees and destroying forests to expand their habitable area. This reduces animal habitat due to which they are forced to enter into human living space, in search of food, water and shelter.

Little Cyclone: The Story Of A Grizzly Cub Questions And Answers Question 3.
Are animals happy in wild life rehabilitation centres?
Answer:
Animals are brought to the wild life rehabilitation centres to live and be protected for the rest of their lives. But the animals might not be happy in captivity. Although they are provided with good sanitary conditions, sufficient enclosures, proper vet care and appropriate feed, they may definitely miss their natural habitat.

Little Cyclone The Story Of A Grizzly Cub Questions And Answers Question 4.
Can a rehab animal survive in the wild?
Answer:
Most animals are brought into wildlife rehabilitation centres for help. They are so sick or emaciated that their chances for survival are often slim. They are taken care of and treated under captivity only until able to live independently in the wild. Every effort is made to minimize human contact and prevent the taming of rehabilitation patients. So, when they are released back in their wild habitat, they often survive well.

Little Cyclone: The Story Of A Grizzly Cub Book Back Answers Question 5.
How many types of bear do you think are there living in the world today?
Answer:
Today, there are only eight species of bears surviving in the world. Except for Antarctica and Australia, all other continents of the world provide habitats for bears.

Vocabulary:

A. use the following phrases in sentences of your own.

1. earn one’s name – make a name for oneself.
She earned her name in politics, as a powerful leader.

2. in the rear of – at the back of.
Harry was sitting in the rear of seat of his car.

3. to see one fight – to struggle to get through something.
I can see him fighting for his right to vote.

4. devoid of – lacking in.
This apartment is devoid of all comforts.

5. air and manner – to behave in a way that does not show how you really feel.
Audy assumed an air and manner of indifference, whenever her name was mentioned.

6. quick as a flash – very quickly.
He was at her side as quick as a flash.

7. in wild haste – rapidly.
It is very important that decisions are not taken in wild haste.

8. make a pass – make advances to someone.
Men seldom make passes at girls who wear glasses.

B. Now refer a dictionary and find idioms on the following animals, birds and insects. Learn their meanings and share what you have learnt with your class. Try to frame illustrative sentences with those idioms. Find opportunities to use them in your everyday conversations.

1. lion – get the lion’s share – get the greatest percentage.
My aunt got the lion’s share of the inheritance.

2. mouse – as poor as a church mouse – very poor.
My cousin is as poor as a church mouse and never has any money to spend.

3. parrot – as sick as a parrot – To be thoroughly displeased.
Tim was as sick as a parrot to be separated from my family.

4. fox – as sly as a fox – smart and clever.
The manager of our apartment is as sly as a fox.

5. hawk – watching like a hawk – watching something very, very closely.
I’m watching you like a hawk.

6. Snake – nurse a snake in one’s bosom – look after.
I have nursed a snake in my bosom all these years.

7. monkey – I’ll be a monkey’s uncle – I’m very surprised.
Well, I’ll be a monkey’s uncle. I never thought I’d pass that test.

8. dog – dog days – very hot days.
I slept in the basement during the dog days of August.

9. snail – At a snail’s pace – Moving very slowly.
Traffic is moving at a snail’s pace.

10. bee – make a beeline for – go quickly and directly to somebody or something.
My grand mother made a beeline for the food as soon as she arrived

C. Based on your reading, answer the following questions in a paragraph of about 100-150 words each.

Summary Of Little Cyclone The Story Of A Grizzly Cub Question 1.
Describe the appearance of Little Cyclone.
Answer:
Little Cyclone is a grizzly cub from Alaska. He earned his name by the vigour of his resistance to ill-treatment. He was a curious and amusing little cub. It had fluffy hair, two big black eyes which sparkled like jet beads, short and fat nose and high shoulders. But his claws were strong and dangerous and he had a truly grizzly spirit. He did not show any fear to its opponents. He was bom full of courage and devoid of all sense of fear. He was a queer looking gray fellow with a broad head. He could fight any other bear on three seconds’ notice.

Little Cyclone: The Story Of A Grizzly Cub Ppt Question 2.
What does the fight Little Cyclone and his brother put up, tell you about the nature of grizzly bears?
Answer:
Grizzly bears are bom full of courage and devoid of all sense of fear. Little cyclone is a grizzly cub from Alaska. He earned his name by the vigour of his resistance to ill treatment. When his mother was fired at, on a timbered hillside, he and his brother ran away as fast as their short and thick legs could carry them. When they came back,they thought their mother was sleeping. They cuddled up close against her warm body and slept peacefully until morning.

They were awakened by the rough grasp of human hands. Bravely, they bit, scratched and cried aloud with anger. His brother made a fight so fierce and terrible that his nervous captor let him go. Although, Little Cyclone fought just as desperately, his captor seized him by his hind legs, dragged him backwards and bound him. This fight of the grizzly bears proves their strength and grit. They do not wish to be cowed down or dominated by their opponents.

Little Cyclone: The Story Of A Grizzly Cub Mind Map Question 3.
“If any of you fellows think there is anything coming to you from me, come and take (t”. How did Little Cyclone prove this?
Answer:
When Little Cyclone’s travelling box was opened, he found himself free in the Bear Nursery at New York. He walked stiffly with pride to the centre of the stage, halted and calmly looked about him. His air and manner said as plainly as English, “I’m a grizzly from Alaska, and I’ve come to stay. If any of you fellows think there is anything coming to you from me, come and take it’. Usually a new comer would be badly scared during his first day in the Nursery and very timid during the next. But grizzlies are different. They are born full of courage and devoid of all sense of fear.

Naturally, it is a good test of courage and temper to turn a new bear into that roistering crowd. But Little Cyclone was fearless and quick in attacking his opponents on three seconds’ notice.

Little Cyclone The Story Of A Grizzly Cub Ppt Question 4.
Describe the confrontation between Little Czar and Little Cyclone.
Answer:
Little Czar was a very cheeky and impertinent bear. But it was a good-natured European brown bear. He walked to Little Cyclone and aimed a sample blow at Cyclone’s left ear. Quick as a flash, outshot Cyclone’s right paw, as only a grizzly can strike and caught the would-be hazer on the side of the head. Amazed and confused, Czar fled in wild haste. Next Cyclone also attacked a black bear cub, who made a pass at the newcomer and made him to quit the field.

Little Cyclone carefully and meticulously met every attack, real or faked, that was made upon him. All the bears in the Nursery understood that Little Cyclone can fight any other bear on three seconds’ notice. He could also strike anyone hard and quickly.

D. Telling the Story Again.

Little Cyclone was a grizzly cub from __________ (1) ___________. earned his name __________ (2) _________. When his mother was fired at, they ____________ .(3) ___________. The next day at sunrise the two orphans found themselves at _____________ (4) _____________ .One of them escaped ____________ (5) _____________. So the captor let him go. But the other cub was ____________ (6) ___________ and taken to the ___________ (7) ___________ at New York. The Zoological Park had _____________ (8) _____________ . Usually a newcomer is badly scared on his first day but ______________ (9) ______________. When the box was opened he stood up with courage __________(10) ____________.  Cyclone courageously met every __________________ (11) ___________ In less than an hour, all the other bears understood _________ (12) ____________. From then on Little Cyclone’s position was _____________ (13) _____________.
Answer:

1. Alaska, who
2. by the vigour of his resistance to ill-treatment.
3. ran away as fast as their stumpy legs could carry them.
4. the rough grasp of human hands.
5. after a fierce and terrible fight,
6. seized
7. Zoological Park
8. Bears’ Nursery.
9. grizzly bears are different
10. and walked stiffly with pride to the center of the stage, halted and calmly looked about him.
11. attack real or faked.
12. that Cyclone could strike quick and hard and fight any other bear on three seconds’notice.
13. assured with respect and dignity.

E. Choose the correct answer.

Little Cyclone The Story Of A Grizzly Cub In Tamil Question 1.
Little Cyclone is a grizzly cub who earned his name by his ____________.
(a) appearance and behaviour.
(b) viguor of resistance to ill-treatment.
(c) speed and courage.
(d) escape from a cyclone.
Answer:
(b) vigour of resistance to ill-treatment

Little Cyclone The Story Of A Grizzly Cub Mind Map Question 2.
The nervous captor let one bear go because ____________.
(a) he was afraid of bears.
(b) he did not have proper equipment to seize him.
(c) he bear fought so fiercly.
(d) the bear escaped and ran away.
Answer:
(c) the bear fought so fiercly

The Story Of A Grizzly Cub Summary Question 3.
Little Cyclone was rescued by the ____________.
(a) members of the Blue Cross.
(b) friendly hands of the Zoological Society.
(c) members of the National Zoo.
(d) volunteers from New York.
Answer:
(b) friendly hands of the Zoological Society

Question 4.
Little Czar was a ____________.
(a) good natured European brown bear.
(b) grizzly cub from Alaska.
(c) furry little Polar bear.
(d) North American black bear.
Answer:
(a) good natured European brown bear

Question 5.
Little Cyclone will fight any other bear in ____________.
(a) 10 minutes’ notice.
(b) 15 minutes’ notice.
(c) 03 seconds’ notice.
(d) 10 seconds’ notice.
Answer:
(c) 03 seconds’ notice

F. Learn the following idioms on bears.

Little Cyclone: The Story of a Grizzly Cub About The Author:

William Temple Homaday was an American Zoologist, conservationist, taxidermist and author. The first director of the New York Zoological Park, William Temple Homaday was a pioneer in the early wildlife conservation movement in the United States.

He is known for his dramatic ‘life groups” of animals in natural setting for museum displays. Homaday’s goal was to educate the American people about these magnificent animals and generate interest in environmental conservation. He also produced a very popular exhibit of a bison group for the National Museum.

In 1889, Homaday published ‘The Extermination of the American Bison’ a popular work that did create public support to save this species. He emphasized the importance of saving American native wildife.

Little Cyclone: The Story of a Grizzly Cub Summary:

A young grizzly bear by name Little Cyclone had proved its strength and grit. Little Cyclone did not cow down nor let the bigger bears to dominate it. Little Cyclone is from Alaska. It earned this name after it showed its vigour of resistance to ill-treatment.

One day when Little Cyclone’s mother was fired at a timbered hillside facing Chilkat River, he and his brother ran to the spot and cuddled her thinking that she was asleep the whole night. The next day, before dawn the two brothers were seized by humans.

One of them escaped from the human hand by making a terrible and forceful fight and stayed in Chilkoot. The other failed in its endeavour and was captured and seized. Then it was collared, chained in the rear of the saloon in Porcupine city. To tame the grizzly cub they used a long pole and violently prodded to see if it defended. Very soon Little Cyclone was rescued by die zoological society’s field agent who took him to New York.

In New York at the Bears’ Nursery, which is a big yard, it had a shade tree, a tree to climb, a swimming pool, three sleeping dens and a rock cliff where usually six to eight cubs were accommodated. Naturally it is a good test of courage and temper to turn a new bear into that roystering crowd.

A newcomer generally in a nursery takes time to adapt but grizzlies are different. Especially Little Cyclone’s behaviour was very different. When he was let out from the travelling box, he stalked and occupied the centre stage with an air and manner which pronounced thus: “I’m a grizzly from Alaska, and I’ve come to stay.” His mannerism also stated that if you dare to protest come for a fight.

Little Czar, a very saucy but good. natured European brown bear cub gave a blow at Little Cyclone’s left ear. Quick as a flash, Cyclone’s right paw struck Czar and caught the side of the head. Amazed and confounded Czar fled. Next came a black bear cub twice the size of Cyclone but he received a fierce blow that he immediately left the field and ran to the top of the cliff.

There were lots of attack at Cyclone one after the other but in less than an hour every bear in the Nursery understood that Little Cyclone, the queer looking gray fellow with broad head and short nose could strike quick and hard and finish them off in less than three seconds. From that time, Cyclone’s position was assured.

Little Cyclone: The Story of a Grizzly Cub Glossary:

Students can Download English Poem 2 My Computer Needs A Break Questions and Answers, Summary, Activity, Notes, Samacheer Kalvi 8th English Book Solutions Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus and score more marks in your examinations.

Tamilnadu Samacheer Kalvi 8th English Solutions Term 3 Poem Chapter 2 My Computer Needs A Break

Read And Understand

A. Answer the following.

My Computer Needs A Break Question 1.
How does the poet describe her computer?
Answer:
The poet describes her computer as very intelligent and smart. The computer seems to know a lot of information by heart.

My Computer Needs A Break Poem Question 2.
What happened to the computer?
Answer:
The computer was behaving badly, forgets to save and store anything. A virus has got into it and it became sick.

My Computer Needs A Break Summary Question 3.
List four things that the computer could not do after it became absent-minded.
Answer:
(a) The computer forgets to save the poet s work.
(b) It doesn’t check her spellings.
(c) It hides all her files.
(d) It makes her work vanish in the most dreadful way.

My Computer Needs A Break Poem Summary Question 4.
What made the poet squirm?
Answer:
When the computer actually gobbled a worm, a virus, it behaved unsteadily. So the poet squirmed.

My Computer Needs A Break Question Answer Question 5.
Why did the poet call the doctor?
Answer:
The computer caught a virus and fell very sick. So the poet had to call a doctor.

B. Fill in the blanks.

1. Computers are ________ and ________
2. We get answers for questions by a ________
3. The computer forgot to ________ the poet’s work.
4. The computer actually gobbled a ________
5. The poet feels that his computer needs ________

Answer:

1. brainy, smart
2. click
3. save
4. worm
5. a holiday

C. Pick out the rhyming words from the poem.

1. Smart – ______
2. click – ______
3. right – ______
4. sick – ______

Answer:

1. heart
2. quick
3. sight
4. quick

D. Match the poetic lines with Figures of speech

1. So brainy – (a) personification
2. Mountains – (b) personification
3. It’s so absent minded – (c) hyperbole
4. Computer gobbled a worm – (d) metaphor
5. Very sick – (e) metaphor

Answer:

1. (d)
2. (c)
3. (a)
4. (b)
5. (e)

E. Find the alliterating words from the poem

1. Save – ______
2. Doctor – ______
3. Virus – ______
4. makes – ______

Answer:

1. store
2. double
3. very
4. most

Parallel Reading

My Computer Needs A Break Book Back Answers Additional Questions:

My Computer Needs A Break Poem Questions And Answers Question 1.
Who bought us closer and then made us more distance?
Answer:
Technology brought us closer and then made us more distance.

My Computer Needs A Break Poem Lines Question 2.
What did technology do?
Answer:
It introduced us to more friends and invited enemies. It gave us more publicity and exploited us. It saved us more and it is spent to be more busy.

My Computer Needs A Break Poem Explanation Question 3.
What does the poet say about the Technology?
Answer:
The technology is an entrapping blessing in disguise.

My Computer Needs A Break Poem Question Answer Question 4.
Which is our new addiction?
Answer:
Technology is our new addiction.

My Computer Needs A Break Poem Lesson Plan Question 5.
Can we live without Technology?
Answer:
No, we cannot live without technology.

My Computer Needs A Break Additional Questions

I. Poem Comprehension:

My Computer Needs A Break Poem By Santhini Govindan Question 1.
My computer has always been so brainy and smart – It seems to know mountains of information by heart.

(a) What has the computer always been to the poet?
Answer:
The computer had always been so brainy and smart.

(b) Why does the poet use the word ‘mountains’?
Answer:
She had used this word to insist that the computer knows a lot of information.

(c) What do you mean by ‘brainy’.
Answer:
‘Brainy’ means “intelligent”.

8th English My Computer Needs A Break Question 2.
It forgets to ‘save’ my work, and store it away,
And instead, makes it vanish in the most dreadful way.

(a) What does the computer forget?
Answer:
The computer forgets to save the poet’s work.

(b) What vanishes in the most dreadful way?
OH Her works vanish in the most dreadful way.

(c) What do you mean by the word “dreadful”?
Answer:
“Dreadful” means “unpleasant”.

II. Poem Appreciation:

Question 1.
If I type in a question, and give my mouse a click,
My computer always gives me the answer really quick!

(a) Pick out the rhyming words.
Answer:
click – quick are the rhyming words.

(b) Name the alliterated words.
Answer:
my – mouse are the alliterated words.

Question 2.
And one day, my naughty computer actually gobbled a worm,
And behaved so erratically that it made me squirm.

(a) What is the figure of speech used here?
Answer:
Personification is used here. The computer is given human traits. It gobbled a worm.

(b) Pick out the alliterated words.
Answer:
made – me are the alliterated words.

III. Very Short Questions and Answers.

Question 1.
What do you mean by phrase “mountains of information”?
Answer:
It means a lot of information.

Question 2.
Who is absent-minded?
Answer:
The poets computer is absent-minded.

Question 3.
What do you mean by the word “erratically”?
Answer:
“Erratically” means “unsteadily or unpredictably”.

Question 4.
Why did the computer fall very sick according to the poet?
Answer:
The computer fell very sick because it caught a virus.

Question 5.
What vanished from the poet’s sight?
Answer:
Files vanished from the poets sight.

IV. Short Questions and Answers :

Question 1.
What happened one day?
Answer:
One day, the poet’s computer actually gobbled a worm that was a virus and behaved so unsteadily. This made the poet discomfort.

Question 2.
Why did the poet call a doctor?
Answer:
The poet called in a doctor to examine her computer which caught a virus and fell
very sick.

Question 3.
Why did the poet say that she didn’t know what to do?
Answer:
Her computer behaved badly and became absent-minded. So the poet said that she didn’t know what to do.

V. Paragraph Question with Answer.

Question 1.
What are the problems faced by the poet with her computer?
The poet’s computer had always been so intelligent and fashionable. It gave a lot of information quickly. But after some days, it gave her a lot of problems. She says that it was absent-minded. She did not know what to do about it. It forgot to save her work and store it away. It made her work vanish in the most unpleasant way. It didn’t check her spellings. It hid her files and vanished them from her sight. One day it gobbled a virus and fell very sick. So she had to call a doctor (a technician) to set it right.

Warm Up

Question 1.
In pairs, tell each other how computer plays a vital role in all fields.
Answer:

1. Computer helps students to learn new things.
2. It is a boon to modern society.
3. It is widely used in all fields such as Economics, Science, Medical, Law,Engineering, Designing, Graphics and Film making etc.
4. Computer literacy is vital to success in today’s world.
5. Computers have helped in the design of safety equipment in sports.

My Computer Needs A Break Summary

The poet’s computer had always been very intelligent and fashionable. It seemed to know a lot of information by heart. If she typed a question and gave her mouse a click, it gave her the answer quickly. But recently, her computer had been behaving badly. It was so absent-minded and forgot to save her work and store it. Instead, her work vanished in the most dreadful way. It also didn’t check her spellings and hid her files, vanishing them from sight.

One day, the naughty computer actually swallowed a worm, that is a virus and behaved so unsteadily. The poet was in a discomfort. As it caught the virus, it became sick. So she had to call the doctor (technician) to examine her computer. She just asked him whether his tired computer needed some relaxations (break) because she had been using it for many days.

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Tamilnadu Samacheer Kalvi 11th English Solutions Supplementary Chapter 1 After Twenty Years

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11th English Supplementary Reader Paragraph Warm up

(a) What do you expect your close friends to do for you? Beautify the petals with your thoughts?

Answer:

1. 1. Educate
   2. help

1. encourage
2. support
3. share
4. care
5. guide

11th English After Twenty Years Paragraph Questions (b)

After Twenty Years Questions And Answers Pdf Question (i)
Find out when the International Day of Friendship is celebrated.
Answer:
International day of friendship is celebrated every year on 30 July.

After Twenty Years Paragraph Question (ii)
How is that day celebrated?
Answer:
Activities on a friendship day:

• Cards indicating how one values the other’s friendship are handwritten and exchanged.
• Friends exchange small gifts such as flowers, cakes, chocolates and friendship bands.
• Call and greet “Happy Friendship Day” or at least SMS the greeting.
• Buy a ticket for a movie to show how one values the other.
• Take a group photograph and upload it on social media.

Samacheer Kalvi 11th English After Twenty Years Textual Questions

(1) Answer the following questions in a sentence or two each, based on your understanding of the story:

After Twenty Years Question Answer Class 11 Question (a)
Describe the appearance of the policeman on the beat.
Answer:
The policeman on the beat was strong. He had a well-built physique. He had an air of authority about. He had a sense of pride of being a guardian of peace and walked with a swagger.

After Twenty Years Questions And Answers Question (b)
What did he keep doing while on his rounds?
Answer:
On his rounds, the policeman checked the door knobs of shops to ensure that every shop was safe. He carefully watched down the pacific through fare.

After Twenty Years Summary In Tamil Question (c)
Why were the streets devoid of people?
Answer:
It was 10 ‘O’ clock at night. Most of the shops were closed. It was chill. It appeared that it might rain soon as the gusts of winds were very chill with the taste of rain. So, the streets were devoid of people.

After Twenty Years Question And Answer Question (d)
What story did the man standing near the hardware store tell the passing cop?
Answer:
The stranger told the cop that himself and Jimmy Wells, his best friend dined at Big Joe Brady’s restaurant and decided to meet there after twenty years that day at 10 p.m. If Jimmy were alive, he would definitely meet him there. They had both decided that twenty years was long enough to make one’s fortune. Jimmy Wells stayed in New York and he had gone to the west.

11th English After Twenty Years Summary Question (e)
What used to be there in the place of that shop twenty years ago?
Answer:
In the place of the shop twenty years ago, Big Joe Brady’s restaurant was there.

11th English Supplementary Reader In Tamil Question (f)
Describe the man awaiting the arrival of his friend.
Answer:
The waiting man was pale and had a square jawed, face with keen eyes. There was a little scar near his right eyebrow. His scarf pin was a large diamond oddly set.

11th English Supplementary After Twenty Years Question (g)
Why did the friends part ways?
Answer:
Both parted ways to seek out their fortunes. Jimmy refused to leave New York. But Bob took the risk and the went to the west to seek his fortune.

After Twenty Years Questions Question (h)
When and how did Bob realize that the tall man was not his friend?
Answer:
A drug store stood at the comer. It was brilliant with electric lights. When Bob and the tall man came into this glare, they simultaneously gazed upon each other. It was then Bob realized that the man in the overcoat was not Jimmy Wells.

After Twenty Years Class 11 Question (i)
Who was the tall man?
Answer:
The tall man was another policeman in plain clothes. He had been sent by Jimmy Wells to arrest Bob.

After Twenty Years Hints Development Question (j)
What did he give Bob?
Answer:
He gave Bob a note written by Jimmy Wells.

2. State whether the following statements are true or false by marking ‘✓’ or ‘✗’ in the corresponding boxes:

(a) The cop suddenly slowed his walk, when he heard the barking of dogs.
(b) The friends grew up together in the city of New York.
(c) Both Jimmy and Bob were of the same age.
(d) The friends parted one night after watching a movie together.
(e) The friends could not keep in touch because they lost each other’s phone numbers.
(J) Bob wanted to stay for half an hour more than the appointed time.
(g) Jimmy grew a little taller after he was twenty.
(h) Bob realised that the tall man was not Jimmy Wells from the shape of his nose.
Answer:
(a) False
(b) True
(c) False
(d) False
(e) False
(f) True
(g) False

(3) What does each of the following mean in the story? Choose the right option.

Question (a)
on the beat:
(i) moving around hitting everyone with a stick
(ii) on duty walking around the assigned area
(iii) marching with his heart beating fast
Answer:
(ii) on duty walking around the assigned area

Question (b)
a guardian of peace:
(i) a watchman
(ii) a holy man
(iii) a policeman
Answer:
(iii) a policeman

Question (c)
arm in arm:
(i) with arms linked together
(ii) with weapons in hands
(iii) with handcuffs on wrists
Answer:
(i) with arms linked together

Question (d)
plainclothes man:
(i) a man who wears simple clothes for grand occasions
(ii) a policeman in civilian clothes while on duty
(iii) a cine artist in ordinary costumes
Answer:
(ii) a policeman in civilian clothes while on duty

(4) Answer the following questions in three or four sentences each:

Question (a)
What did Bob share with the cop about their friendship?
Answer:
Bob said that Jimmy Wells and himself were like brothers. Both were raised in New York. He was eighteen and Jimmy was twenty. He couldn’t drag Jimmy to west because Jimmy, the plodder thought New York was the only place on earth. He believed that Jimmy would meet him at the appointed place as he was his best friend.

Question (b)
Answer:
What are the strengths and weaknesses of Jimmy Wells from Bob’s point of view? Jimmy Wells was assertive. He did not want to leave New York. But he was not adventurous enough to chase his dreams, across the nation. He was a plodder.

Question (c)
Was Bob hopeful of his friend’s arrival? How do you know?
Answer:
Bob was really hopeful of his friend’s arrival. He told the patrolman that he would wait for his best chum for another half an hour. He added that Jimmy would meet him there if he were alive for he was always the truest, staunchest old chap in the world.

Question (d)
How did the cop come to understand that Bob had been successful in the West?
Answer:
In the cigar light, Jimmy Wells saw Bob wearing a Diamond studded watch and a scarf pin too. He was wearing a very costly dress too. He admitted that he did pretty well in the west. He expected Jimmy too to be at  least half successful compared to him. Thus the cop understood that Bob had been successful in making money.