The enthalpy of hydrogenation of cyclohexene is −119.5kJ/mol. What is the enthalpy of benzene, if its resonance energy is −150.4kJ/mol?
A
−269kJ/mol
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
−358.8kJ/mol
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
−508.9kJ/mol
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
−208.1kJ/mol
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
Open in App
Solution
The correct option is D−208.1kJ/mol Enthalpy of hydrogentaion of cyclohexene = −119.5kJ/mol ∴ calculated enthalpy of hydrogenation of benzene is: 3(−119.5)=−358.5kJ/mol
Since the actual value should be lower by an amount equal to resonance energy, actual enthalpy of hydrogenation is =−358.5kJ/mol−(−150.4kJ/mol) =−208.1kJ/mol