Question

Aicharya · Accepted Answer

$\begin{aligned} & \Delta \mathrm{T}_{\mathrm{f}}=\mathrm{ik}_{\mathrm{f}} \mathrm{m} \ & 0.2=\mathrm{i} 	imes 1.8 	imes 0.1 \ & \mathrm{i}=\frac{20}{18}=\frac{10}{9} \ & 	ext { For } \mathrm{HA}_{(\mathrm{aq})} ightleftharpoons \mathrm{H}_{(\mathrm{aq})}^{+}+\mathrm{A}_{(\mathrm{aq})}^{-} \ & \mathrm{t}=0 \quad 1 \ & \mathrm{t}=\mathrm{t}_{\mathrm{eq}} 1-\alpha \quad \alpha \ & \mathrm{i}=1+\alpha \ & \frac{10}{9}=1+\alpha \ & \alpha=\frac{1}{9} \ & \mathrm{~K}_{\mathrm{eq}}=\frac{\left[\mathrm{H}^{+}ight]\left[\mathrm{A}^{-}ight]}{[\mathrm{HA}]}=\frac{\mathrm{C} \alpha^2}{1-\alpha} \ & 0.1\left(\frac{1}{9}ight)^2 \ & =\frac{1}{1-\frac{1}{9}}=\frac{1}{720} \ & \mathrm{~K}_{\mathrm{eq}}=1.38 	imes 10^{-3}\end{aligned}$

Solution