(a) What is a homologous series ? Explain with an example.
(b) Define the following terms giving one example of each.
(i) Esterification
(ii) Addition reaction
(a) Homologous series is a group of compounds which have the same functional group , same general formula and where to successive member differ by – CH2 in the molecular formula
Example of Homologous series is : CH3-OH and CH3 -CH2-OH Functional group : -OH , General Formula : CnH2nOH and successive member differ by – CH2
(b) Esterification : The reaction of carboxylic acid with an alcohol in the presence of H2SO4 yields an ester.
CH3COOH+C2H5OH -------> CH3COOC2H5 (Ester) + H2O
Addition Reaction : A reaction in which two or more atoms are added across a double or triple bond in presence of catalyst is called addition reactions.
CH2=CH2+H2 ---(Pt./Pd or Ni)---> CH3-CH3