Calculate enthalpy change (in kJ) when 2 moles of liquid acetic acid undergoes dissociation into CH4(g) and CO2(g) from the following data. ΔHvap [CH3COOH](ℓ) = 50 kJ/mol. Resonance energy of CH3COOH(g) = – 50 kJ/mol Resonance energy of CO2(g) = – 25 kJ/mol Bonding energy (kJ/mol) : C–H = 400; C – O = 350; O = O = 500 C–C = 350; O – H = 450; C = O = 800; H

Engineering

Chemistry

Enthalpy of Neutralisation and Resonance Energy

Question

Calculate enthalpy change (in kJ) when 2 moles of liquid acetic acid undergoes dissociation into CH₄(g) and CO₂(g) from the following data.

ΔH_vap [CH₃COOH](ℓ) = 50 kJ/mol.
Resonance energy of CH₃COOH(g) = – 50 kJ/mol
Resonance energy of CO₂(g) = – 25 kJ/mol
Bonding energy (kJ/mol) :

C–H = 400; C – O = 350; O = O = 500
C–C = 350; O – H = 450; C = O = 800; H – H = 400

LiveFree JEE Main Previous Year Online Papers Live Free JEE Advance Previous Year Online Papers

College PredictorLive

Know your College Admission Chances Based on your Rank/Percentile, Category and Home State.

Get your JEE Main Personalised Report with Top Predicted Colleges in JoSA

$ΔH = 2 {ΔH}_{vap {CH}_{3} COOH (ℓ)} + 2 | resonance {energy}_{{CH}_{3} COOH} |$
$+ 2 [3 {BE}_{C - H} + {BE}_{C - C} + {BE}_{C = O} + {BE}_{C - O} + {BE}_{O - H}]$
$- 2 [4 {BE}_{C - H}] - 2 | resonance energy_{{CO}_{2}} | - 2 {BE}_{C = O}$
ΔH = 2 × 50 + 2 × 50 + 2 [3 × 400 + 350 + 800 + 350 + 450]
– 2 [4×400] – 2 × 25 – 4 × 800
ΔH = 50 kJ