Question

Compound having formula $C_8H_{10}$ forms two isomers $P$ and $Q$. On oxidation $P$ gives benzoic acid and $Q$ gives phthalic acid. The isomers $P$ and $Q$ are

• A.
• B.
• C.
• D.

Answer 1

Answer: (C)

Answer 2

Alk. $KM nO_4$ oxidises the entire side chain of alkyl benzene to $-COOH$ group irrespective of the length of the carbon chain. If there are two or more alkyl groups, each alkyl chain is oxidised to a $-COOH$ group.