The absolute enthalpy of neutralisation of the reaction MgO (s)+2 HCl (a q) longrightarrow MgCl 2(a q)+ H 2 O (l) will be

Question

The absolute enthalpy of neutralisation of the reaction MgO (s)+2 HCl (a q) longrightarrow MgCl 2(a q)+ H 2 O (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

The absolute value of enthalpy of neutralization of this reaction is greater than

- 57.33 k J m o l^{- 1}

.

This is due to the very high enthalpy of hydration of

M g^{2 +}

ion. The change in enthalpy of this reaction is nearly

- 146 k J

.

Thus enthalpy of neutralization per mole of

H^{+}

ion is nearly

- 73 k J

, which is greater than the enthalpy of neutralization strong acid against strong base i.e.

- 57.33 k J

.

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 $- 57.33 k J m o l^{- 1}$

$- 57.33 k J m o l^{- 1}$

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

$57.33 k J m o l^{- 1}$

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

less than −57.33kJmol−1

−57.33kJmol−1

greater than −57.33kJmol−1

57.33kJmol−1

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 $- 57.33 k J m o l^{- 1}$

$- 57.33 k J m o l^{- 1}$

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

$57.33 k J m o l^{- 1}$