Chemistry - Liquid Solution Question with Solution | TestHub

Let initial moles of $\mathrm{HA}$ is $\mathrm{a}$

$$\begin{gathered} 2\mathrm{HA}\to {\mathrm{H}}_2{ \mathrm{A}}_2 \\ 0.5\mathrm{a} 0.25\mathrm{a} \end{gathered}$$

$$\begin{gathered} \mathrm{HA}\rightleftharpoons {\mathrm{H}}^{+}+ {\mathrm{A}}^{-} \\ 0.5\mathrm{a} 0.5\mathrm{a} 0.5\mathrm{a} \end{gathered}$$

Now, $\mathrm{i}=\frac{\text{ final moles }}{\text{ initial moles }}=\frac{0.25\mathrm{a}+0.5\mathrm{a}+0.5\mathrm{a}}{0.5\mathrm{a}+0.5\mathrm{a}}$

$=1.25=125\times {10}^{-2}$