The difference between heats of Reaction at constant pressure and constant volume for the Reaction 2C6H6 + 15O2 → 12CO2 + 6H2O at 25∘C. in kJ is
-7.43
qp − qv = Δ H − Δ E = Δ nRT
(∵ qv = Δ E,W=0)(Δn = 12 − 15 = −3)
= −3 × 8.314 × 10−3 × 298
= −7.43 kJ