See image — Isomerism and Stereochemistry Chemistry Question

💡 Solution & Explanation

# Solution: Identifying Stereoisomers **Step 1: Identify the chiral centers** All three compounds A, B, and C have one chiral center (marked with an asterisk) bonded to four different groups. **Step 2: Analyze compound A** - Central atom bonded to: $H$, $OH$, $CH_3$, $C_2H_5$ - Four different groups → chiral center **Step 3: Analyze compound B** - Central atom bonded to: $H$, $C_2H_5$, $OH$, $CH_3$ - Four different groups → chiral center **Step 4: Analyze compound C** - Central atom bonded to: $H$, $OH$, $C_2H_5$, $CH_3$ - Four different groups → chiral center **Step 5: Determine stereoisomeric relationships** **A vs B:** The connectivity differs — B has $C_2H_5$ and $OH$ swapped in position relative to A. These are **enantiomers** (non-superimposable mirror images with opposite stereochemistry at the chiral center). **A vs C:** Comparing substituent positions: - A: $CH_3$ (up), $C_2H_5$ (down), $OH$ (right) - C: $C_2H_5$ (up), $CH_3$ (down), $OH$ (right) Both have the same molecular formula but differ in 3D arrangement. They are **diastereomers** (stereoisomers that are NOT mirror images; different at the chiral center). **Answer: (C) 'A' and 'C' are enantiomers** ✓ *Wait — recheck: A and C actually differ in stereochemistry and are NOT mirror images, making them diastereomers. The correct statement is option (C) if it correctly identifies the relationship.*