See image — Isomerism and Stereochemistry Chemistry Question

💡 Solution & Explanation

# Solution: Type of Isomerism **Step 1: Identify the molecular formula of both compounds** First compound: $CH_3-CH_2-CH_2-CN$ - Carbon count: 3 (main chain) + 1 (from CN) = 4 carbons - Hydrogen count: 3 + 2 + 2 = 7 hydrogens - Nitrogen count: 1 - **Molecular formula: $C_4H_7N$** Second compound: $CH_3-CH(CN)-CH_3$ (with CN as a substituent on central carbon) - Carbon count: 2 (methyls) + 1 (central) + 1 (from CN) = 4 carbons - Hydrogen count: 3 + 1 + 3 = 7 hydrogens - Nitrogen count: 1 - **Molecular formula: $C_4H_7N$** **Step 2: Confirm they are isomers** Both have identical molecular formula $C_4H_7N$ ✓ **Step 3: Determine the type of isomerism** - **Position isomerism**: The $CN$ group is attached at different positions (terminal position in compound 1 vs. central carbon in compound 2) - **Chain isomerism**: The carbon skeleton is the same (both have 4 carbons in a chain/structure) The key difference is the **position of the functional group** (cyano group), not the carbon chain arrangement. **Answer: (A) Position isomerism** — The $CN$ group occupies different positions on the same carbon chain, making these position isomers.