Check which compound shows optical isomerism.
n-propyl chloride → CH₃–CH₂–CH₂Cl → No chiral carbon.
iso-propyl chloride → (CH₃)₂CHCl → Two identical CH₃ groups → Not chiral.
sec-butyl chloride → CH₃–CHCl–CH₂–CH₃
The second carbon is attached to:
• CH₃
• C₂H₅
• Cl
• H
Four different groups → Chiral → Shows optical isomerism.
neo-pentyl chloride → (CH₃)₃C–CH₂Cl → No chiral carbon.
Thus, sec-butyl chloride exhibits optical isomerism.
Molecular formula of sec-butyl chloride:
C₄H₉Cl
Molar mass:
= 4(12) + 9(1) + 35.5
= 48 + 9 + 35.5
= 92.5 g mol⁻¹
Mass of carbon:
= 4 × 12 = 48 g
Percentage of carbon:
\[ \frac{48}{92.5} \times 100 \]
\[ ≈ 51.9 \% \approx 52 \% \]
Correct Option: C