Tamilnadu Samacheer Kalvi 11th Chemistry Notes Chapter 11 Fundamentals of Organic Chemistry Notes
Organic chemistry – It is the study of compounds of carbon.
Catenation – The tendency of an atom to form a chain of bonds with the atoms of the same element is called catenation.
Functional group – It is an atom or a specific combination of bonded atoms that react in a irrespective of the organic molecule in which it is present.
Homologous series – A series of organic compounds each containing a characteristic functional group and the successive members differ from each other in a molecular formula by a CH2 group is called homologous series.
Alkanes – CnH2n + 2
Alkenes – CnH2n
Alkynes- CnH2n-2
IUPAC – International Union of Pure and Applied Chemistry.
Nuclear substituted aromatic compound – These are the compounds in which the functional group is directly attached to the benzene ring. These are derivatives of benzene.
Molecular formula of an organic compound – It is the simplest, least informative representation, showing the ratio of atoms present.
Structural formula of an organic compound – It is the formula that shows the way of atoms in a compound comiected to each other.
Molecular models – These are physical devices that are used for a better visualisation and perception of three dimensional shapes of organic molecules.
Three dimensional representation of organic molecule – The simplest convention is solid and dashed wedge formula in which 3-D image of a molecule can be perceived from two dimensional picture.
Fisher projection formula – This s a method of representing three dimensional structures in two dimension.
Saw horse projection formula – The bond between two carbon atoms is drawn diagonally and slightly elongated. The lower left hand carbon is considered lying towards the front and the upper right hand carbon is considered lying towards the back.
Newman projection formula – In this formula, the molecules are viewed from the front along the carbon-carbon bond axis.
Isomerism – It is a phenomenon in which two or more compounds with the same molecular formula but different structures and properties are there.
Isomers – Compounds exhibiting the isomerism are called isomers.
Constitutional isomers – These isomers have same molecular formula but differ in their bonding sequence.
Chain (or) nuclear (or) skeletal isomerism – These isomers differ in the way in which the carbon atoms are bonded to each other in a carbon chain.
Position isomerism – Compounds with the same molecular formula and carbon skeleton but differ in the position of substituent are said to exhibit position isomerism.
Functional isomerism – Different compounds having the same molecular formula but different functional groups are said to exhibit functional isomerism.
Metamerism – It is a special kind of structural isomerism arises due to the unequal distribution of carbon atoms on either side of the functional group or different alkyl groups attached to the either side of the same functional group and having the same molecular formula.
Tautomerism – It is a special type of functional isomerism in which a single compound exists in two readily interconvertible structures that differ markedly in the relative position of atleast one atomic nucleus, generally hydrogen.
Stereoisomerism – The phenomenon in which the isomers which have same bond connectivity but different arrangement of groups or atoms in space in known as stereoisomerism.
Geometrical isomerism – The phenomenon in which the stereoisomers which have different arrangement of groups or atoms around a rigid framework of double bonds.
Cis isomer – It is the one in which two similar groups are on the same side of the double bond.
Trans isomer – It is the one in which two similar groups are on the opposite side of the double bond.
Optical isomerism – Compounds having same physical and chemical property but differ only in the rotation of plane of the polarised light are known as optical isomers and the phenomenon is known as optical isomerism.
Dextro rotatory – The optical isomer which rotates the plane polarised light to the right or in clockwise direction is said to be dextro rotatory.
Leavo rotatory – The optical isomer which rotates the plane polarised light to the left or in . anti-clockwise direction is said to be leavo rotatory.
Enantiomers – The optical isomers which rotate the plane polarised light with equal angle but in opposite direction are known as enantiomers.
Chiral carbon – A carbon atom whose tetravalency is satisfied by four different substituents is called asymmetric carbon or chiral carbon.
Sublimation – The process in which the substances on heaving converted directly from solid to vapour without melting is known as sublimation.
Azeotropes – Compounds which are constant boiling mixtures.
Extraction – The process of removing a substance from its aqueous solution by shaking with a suitable organic solvent is termed extraction.
Chromatography – It is selective distribution of the mixture of organic substances between a stationary phase and a moving phase (or) chromatography is defined as a technique for the separation of a mixture brought about by differential movement of the individual compound through porous medium under the influence of moving solvent.
\(R_{f}=\frac{\text { Distance moved by the substance from base line }(X)}{\text { Distance moved by the solvent from base line }(Y)}\)