Question

Given, $C{H}_{3}COOH\left(aq\right)\to C{H}_{3}CO{O}^{-}\left(aq\right)+H^{+}\left(aq\right)$

${\text{ΔH}}_{\text{rxn}}^{\text{o}}\text{=}\text{0}\text{.004}\text{kcal}{\text{gm}}^{-\text{1}}$

Enthalpy change when $1$ mole of $Ba(OH{)}_2$ , a strong base, is completely neutralized by $C{H}_{3}COOH(aq)$ is ( $\Delta H^{{}^{\circ }}$ of neutralization of strong acid with strong base is = $-\text{13}\text{.7}\text{kcal}{\text{mol}}^{-\text{1}}$ )

• A. $-\text{27}\text{.46 kcal/mol}$
• B. $\text{27}\text{.46 kcal/mol}$
• C. $-\text{26}\text{.92}\text{kcal/mol}$
• D. $-\text{13}\text{.46 kcal/mol}$

Answer 1

Answer: (C)

${\text{ΔH}}^{\text{o}}$ ionisaton of ${\text{CH}}_{\text{3}}\text{COOH}\text{=}\text{0}\text{.004}\times \text{60}\text{=}\text{0}\text{.24}\text{kcal/mol}$

$\therefore$ Enthalpy change $=\left(-13.7+0.24\right)\times 2$

$\text{=}-\text{26}\text{.92}\text{kcal}{\text{mol}}^{-\text{1}}$