The enthalpy of neutralisation of oxalic acid by a strong base is -25.4 kcal mol -1. The enthalpy of neutralisation of strong acid and strong base is -13.7 kcal equiv -1. The enthalpy of dissociation of H 2 C 2 O 2 leftharpoons 2 H ++ C 2 O 42- is

Question

The enthalpy of neutralisation of oxalic acid by a strong base is -25.4 kcal mol -1. The enthalpy of neutralisation of strong acid and strong base is -13.7 kcal equiv -1. The enthalpy of dissociation of H 2 C 2 O 2 leftharpoons 2 H ++ C 2 O 42- is (A) 1.0 kcal mol-1  (B) 2.0 kcal mol-1  (C) 18.55 kcal mol-1  (D) 11.7 kcal mol-1

Tardigrade Admin · Accepted Answer

Δ H=Δ H text dissociation +Δ H text neutalisation ∴ Δ H text diss =Δ H-Δ H text neut =-2 × 13.7-(-25.4) =-27.5+25.4=-2.0 kcal mol -1

Q. The enthalpy of neutralisation of oxalic acid by a strong base is $- 25.4 k c a l m o l^{- 1}$ . The enthalpy of neutralisation of strong acid and strong base is $- 13.7 k c a l e q u i v^{- 1}$ . The enthalpy of dissociation of
$H_{2} C_{2} O_{2} ⇌ 2 H^{+} + C_{2} O_{4}^{2 -}$ is

$1.0 k c a l m o l^{- 1}$

$2.0 k c a l m o l^{- 1}$

$18.55 k c a l m o l^{- 1}$

$11.7 k c a l m o l^{- 1}$

$Δ H = Δ H_{dissociation} + Δ H_{neutalisation}$
$∴ Δ H_{diss} = Δ H - Δ H_{neut}$
$= - 2 \times 13.7 - (- 25.4)$
$= - 27.5 + 25.4 = - 2.0 k c a l m o l^{- 1}$

Q. The enthalpy of neutralisation of oxalic acid by a strong base is −25.4kcalmol−1. The enthalpy of neutralisation of strong acid and strong base is −13.7kcalequiv−1. The enthalpy of dissociation of H2​C2​O2​⇌2H++C2​O42−​ is

1.0kcalmol−1

2.0kcalmol−1

18.55kcalmol−1

11.7kcalmol−1