The bond dissociation energy depends upon the nature of the bond and nature of the molecule. If any molecule more than 1 bonds of similar nature are present then the bond energy reported is the average bond energy.
If enthalpy of hydrogenation of `C_(6)H_(6(l)) "into" C_(6)H_(12(l)) " is " -205 kJ` and resonance energy of `C_(6)H_(6(l))` is `-152kJ//mol` then enthalpy of hydrogenation of is ? Answer `Delta H_("vap") " of " C_(6)H_(6(l)), C_(6)H_(10(l)), C_(6)H_(12(l))` all are equal:

Options

A. `-535.5` kJ/mol
B. `-238` kJ/mol
C. `-357` kJ/mol
D. `-119` kJ/mol

Answer

D

Explanation

Heat of hydrogenation of cyclo hexane
`=("Heat of Hydrogenation of Benzene + Resonance Energy")/(3)`
`= (-205 + (-152))/(3) = -199kJ`