For a weak acid, the concentration of H⁺ ions is given by

$$\begin{gathered} HA\leftrightharpoons H^{+} +A^{-} \\ C 0 0 \\ 1-C\alpha C\alpha C\alpha \end{gathered}$$

${\mathrm{K}}_{\mathrm{a}}=\frac{\left[H^{+}\right]\left[A^{-}\right]}{\left[HA\right]}$

$$\begin{gathered} {\mathrm{K}}_{\mathrm{a}}=\frac{{\mathrm{C}}^2{\mathrm{\alpha }}^2}{(1-\mathrm{\alpha })\mathrm{C}} \\ {\mathrm{K}}_{\mathrm{a}}=\frac{{\mathrm{C\alpha }}^2}{1-\mathrm{\alpha }} \\ 1>>>>>\mathrm{\alpha } \\ {\mathrm{K}}_{\mathrm{a}}={\mathrm{C\alpha }}^2 \\ \mathrm{\alpha } =\sqrt{{\mathrm{K}}_{\mathrm{a}}.\mathrm{C}} \end{gathered}$$
K_a= dissociation constant
[H⁺]= concentration of cation
[A⁻]= concentration of anion
[HA]= concentration of acid
the degree of dissociation of this electrolyte to be α.