Question

The mutual heat of neutralisation of 40 g $NaOH$ and $60g{CH}_{3}COOH$ will be

• A. 57.1 kJ
• B. Less than 57.1 kJ
• C. More than 57.1 kJ
• D. 13.7 kJ

Answer 1

The correct option is B Less than 57.1 kJ

$40gNaOH=\frac{40}{40}=1molNaOH$

$60g{CH}_{3}COOH=\frac{60}{60}=1mol{CH}_{3}COOH$

Since acetic acid is a weak acid, some of the heat is utilised to ionize it. So, enthalpy of neutralisation of 1 mol of $NaOH$ by 1 mol ${CH}_{3}COOH$ is less than $57.1kJ.$

Enthalpy of neutralisation of a strong acid by a strong base is always $57.1kJ.$

So, the correct option is $B$