I am not even getting the idea of this

Question

The enthalpy of neutralisation of a weak acid in 1M solution with a strong base is -56.1 kJ/mol.If the enthalpy of ionization of the acid is 1.5kJ/mol and enthalpy of neutralization of teh strong acid with a strong basw is -57.3 kJ/equiv what is the %ionization of the weak acid in molar solution(assume the acid to be monobasic)

Answer 1

Enthalpy of ionization of strong acid 

= 57.3 kj - 56.1 kj = 1.2 kj

Enthalpy of ionization of weak acid

= 1.5 - 1.2

= 0.3

% of weak acid ionization =

= 20%