Is benzene or cyclohexane more stable?

Question

If it is benzene, then how come the heat of hydrogenation of benzene to cyclohexane is an exothermic process which releases energy, indicating that cyclohexane is more stable.

Answer 1

Stability is a matter of the heat of formation. The lower the number the more stable the compound.

Δ_fH^o_liquid

Benzene = 49.26 kJ/mol

Cyclohexane = –156.4 kJ/mol

Lets add two more compounds with 1 and 2 double bonds, respectively.

Cyclohexene = -38.8 kJ/mol

1,3, cyclohexadiene = +71.4 kJ/mol

In order of stability Cyclohexane, Cyclohexene, Benzene,1,3,cyclohexadiene.