Alkali metal salts of carboxylic acids also undergo decarboxylation
on electrolysis of their aqueous solutions and form hydrocarbons having
twice the number of carbon atoms present in the alkyl group of the acid The reaction is known as Kolbe electrolysis (Unit 9, Class XI) 1 Halogenation
Carboxylic acids having an a-hydrogen are halogenated at the
a-position on treatment with chlorine or bromine in the presence of
small amount of red phosphorus to give a-halocarboxylic acids