JEE Main202621 January 2026Evening ShiftChemistryGeneral Organic ChemistryActual
Given below are four compounds : (a) n-propyl chloride (b) iso-propyl chloride (c) sec-butyl chloride (d) neo-pentyl chloride Percentage of carbon in the one which exhibits optical isomerism is :
Options
- A56
- B40
- C52
- D46
Correct answer
C. 52
Step-by-step solution
Optical isomerism occurs when a compound has a chiral center (asymmetric carbon). Examining each compound: n-propyl chloride (CH3CH2CH2Cl) has no chiral center, iso-propyl chloride (CH3CHClCH3) has no chiral center, sec-butyl chloride (CH3CH2CHClCH3) has one chiral center attached to four different groups, and neo-pentyl chloride has no chiral center. Therefore, sec-butyl chloride exhibits optical isomerism. For C4H9Cl: molar mass = 4(12) + 9(1) + 35.5 = 92.5 g/mol. Carbon percentage = (48/92.5) × 100 = 51.89% ≈ 52