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The standard enthalpy of formation of liquid acetic acid ( CH ₃ COOH ) is -484 kJ mol ⁻¹ . The standard enthalpies of combustion of carbon (graphite) and dihydrogen gas are -394 kJ mol ⁻¹ and -286 kJ mol ⁻¹ respectively. The magnitude of the standard enthalpy of combustion of liquid acetic acid is _____ kJ mol ⁻¹ .

Correct answer

876

Step-by-step solution

The balanced chemical equation for the combustion of liquid acetic acid is: CH ₃ COOH(l) + 2 O ₂ (g) 2 CO ₂ (g) + 2 H ₂ O(l) The standard enthalpy of combustion is given by: _c H^ = _f H^ ( products ) - _f H^ ( reactants ) _c H^ = [2 _f H^ ( CO ₂) + 2 _f H^ ( H ₂ O )] - [ _f H^ ( CH ₃ COOH )] The standard enthalpy of formation of CO ₂ (g) is equal to the standard enthalpy of combustion of carbon (graphite), which is -394 kJ mol ⁻¹ . The standard enthalpy of formation of H ₂ O(l) is equal to the standard enthalpy of

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