question_answer

\[{{\Delta }_{f}}{{H}^{\bigcirc -}}\] of Cyclohexene and benzene at \[25{}^\circ C\]is \[-156\] and \[+49\,kJ\,mo{{l}^{-1}},\] respectively. \[{{\Delta }_{f}}{{H}^{\bigcirc -}}{{\Delta }_{hydrogenation}}{{H}^{\bigcirc -}}\]cyclohexene at \[25{}^\circ C\]is \[-199\,kJ\,\,mo{{l}^{-1}}\] (Resonance energy of benzene is found to be\[-38x\,\,kJ\text{ }mo{{l}^{-1}}.\]) Find the value of x.

Answer:

4