Question

Which type of isomerism is observed between I and II?

• A. Chain isomerism
• B. Position isomerism
• C. Functional isomerism
• D. Metamerism

Answer 1

The correct option is C Functional isomerism

Functional isomers are structural isomers that have same molecular formula but different functional group.
In (I), the compound has amide functional group $-NHCO-$.
In (II), the compound has amine $-N{H}_2$ and aldehyde $-CHO$ functional group. Thus (I) and (II) are functional isomers. Thus, they show functional isomerism.