∴ Heat of hydrogenation of cyclohaxene =−119.5 kJ/mol ∴ Heat of hydrogenation of benzene =3×−119.5=−358.5 kJ/mol Resonance energy = Observed ΔH− Calculated ΔH =−150.4=−358.5−x x=−208.1 kJ Related Theory The energy calculated for a resonance hybrid is lower than the energies of any of the alternative structures; the molecule is then said to be stabilized by resonance.
The enthalpy of hydrogenation of cyclohexene is -119.5 ~kJ ~mol^-1. If resoance energy of benzene is -150 kJ mol^-1, its enthalpy of hydrogenation…
NEET UG 2006 — Chemistry Physical Chemistry
2006mcqmedium
The enthalpy of hydrogenation of cyclohexene is −119.5 kJ mol−1. If resoance energy of benzene is -150 kJmol−1, its enthalpy of hydrogenation would be:
Official previous-year question
Held on 30 Apr 2006 · Verified 9 Jul 2026.
Options
- A
−358.5 kJ mol−1
- B
−508.9 kJ mol−1
- C
−208.1 kJ mol−1
- D
−269.9 kJ mol−1
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