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JEE Main levelSingle correct optionDifficulty 2 of 3g1199

Which of the following C-H bonds has the lowest bond dissociation energy?

Athe $CH X_{3}$ of toluene, $C X_{6} H X_{5} - CH X_{2} - H$
Bthe secondary C-H of propane, $(CH X_{3}) X_{2} CH - H$
Cethane, $CH X_{3} CH X_{2} - H$
Dmethane, $CH X_{3} - H$

Answer: A

Bond dissociation energy is lowest when the radical formed is most stable. Toluene gives the benzyl radical, delocalised over the ring by resonance, which is better than the methyl, ethyl or isopropyl radicals formed from the other compounds.

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