Two isomers A and B with Molar mass 184 g / mol and elemental compositio C , 52 . 2 % ; H , 49 % and Br 42 . 9 % gave benzoic acid and p - bromobenzoic acid, respectively on oxidation with KMnO 4 . Isomer ' A ' is optically active and gives a pale yellow precipitate when warmed with alcoholic AgNO 3 . Isomer ' A ' and ' B ' are, respectively :

Step-by-step solution

Based on the percentage composition of the elements given the molecular formula of the compound is C 8 H 9 Br And the degree of unsaturation or double bond equivalent of C 8 H 9 Br is 4. It is mentioned that A is optically active and gives pale yellow precipitate with AgNO 3 . Hence, the structures of A and B can be deduced based on the following reactions.