Q. C – H bond energy is about101 kcal/mol for methane, ethane and other alkanes but is only77 kcal/mol for C – H bond of $CH_{3}$ in toluene. This is because
A) Of inductive effect due to –$CH_{3}$ in toluene
B) Of the presence of benzene ring in toluene
C) Of resonance among the structures of benzyl radical in toluene
D) Aromaticity of toluene
Explanation
(c)
$\because$ C – H bond in toluene has partial double bond character due to resonance.
∴ C – H bond in toluene has less energy as compared to others.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.