The absolute enthalpy of neutralisation of the reaction `MgO(s)+2HCl(aq)rarrMgCl_(2)(aq)+H_(2)O(l)` will be

Options

A. Less than -57.33 kJ `mol^(-1)`
B. `-57.33 kJ mol^(-1)`
C. Greater than `-57.33 kJ mol^(-1)`
D. `57.33 kJ mol^(-1)`

Answer

A

Explanation

Heat of neutralization will be less than `-57.33 kJ//"mole"` because some amount of this energy will be required for the dissociation of weak base (MgO)