The absolute enthalpy of neutralisation of the reaction, MgO(s)+2HCl(aq) xrightarrowMgCl2(aq)+H2O(l) will be

Question

The absolute enthalpy of neutralisation of the reaction, MgO(s)+2HCl(aq) xrightarrowMgCl2(aq)+H2O(l) will be (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

Tardigrade Admin · Accepted Answer

Heat of neutralisation of strong acid and strong base is -57.33 kJ. MgO is a weak base while HCl is a strong add, so the heat o neutralisation of MgO and HCl is lower than -57.33 kJ because MgO requires some heat in ionisation, then net released amount of heat is decreased.

Q. The absolute enthalpy of neutralisation of the reaction, $M g O (s) + 2 H Cl (a q) M g C l_{2} (a q) + H_{2} O (l)$ will be

less than -57.33 kJ $m o l^{- 1}$

-57.33 kJ $m o l^{- 1}$

greater than -57.33 kJ $m o l^{- 1}$

57.33 kJ $m o l^{- 1}$

Heat of neutralisation of strong acid and strong base is -57.33 kJ. MgO is a weak base while HCl is a strong add, so the heat o neutralisation of MgO and HCl is lower than -57.33 kJ because MgO requires some heat in ionisation, then net released amount of heat is decreased.

Q. The absolute enthalpy of neutralisation of the reaction, MgO(s)+2HCl(aq)​MgCl2​(aq)+H2​O(l) will be

less than -57.33 kJ mol−1

-57.33 kJ mol−1

greater than -57.33 kJ mol−1

57.33 kJ mol−1

Heat of neutralisation of strong acid and strong base is -57.33 kJ. MgO is a weak base while HCl is a strong add, so the heat o neutralisation of MgO and HCl is lower than -57.33 kJ because MgO requires some heat in ionisation, then net released amount of heat is decreased.

Q. The absolute enthalpy of neutralisation of the reaction, $M g O (s) + 2 H Cl (a q) M g C l_{2} (a q) + H_{2} O (l)$ will be

less than -57.33 kJ $m o l^{- 1}$

-57.33 kJ $m o l^{- 1}$

greater than -57.33 kJ $m o l^{- 1}$

57.33 kJ $m o l^{- 1}$