See image — Isomerism and Stereochemistry Chemistry Question

💡 Solution & Explanation

# Analysis of Isomerism **Step 1: Identify the molecular formulas** First compound: $CH_3CHOHCH_2CHO$ - Count: C = 4, H = 8, O = 2 → $C_4H_8O_2$ Second compound: $CH_3CH_2CH_2COOH$ - Count: C = 4, H = 8, O = 2 → $C_4H_8O_2$ Both have the **same molecular formula**, so they are isomers. **Step 2: Identify functional groups** - First compound: Contains $-OH$ (hydroxyl) and $-CHO$ (aldehyde) - Second compound: Contains $-COOH$ (carboxylic acid) **Step 3: Classify the type of isomerism** The two compounds have: - Different functional groups (alcohol + aldehyde vs. carboxylic acid) - Same molecular formula but different chemical properties - Different structural arrangements due to different functional groups This is characteristic of **functional isomerism**, where isomers differ in the type or arrangement of functional groups. **Why other options are wrong:** - **(1) Position isomers**: Differ only in position of the same functional group (e.g., 1-propanol vs. 2-propanol) - **(2) Metamers**: Differ in position of heteroatom relative to the functional group - **(3) Optical isomers**: Non-superimposable mirror images (chiral centers required) **Answer: (4) Functional isomers** ✓