The specific conductance of 0.0025 M acetic acid is 5 × 10^-5 S cm^-1 at a certain temperature. The dissociation constant of acetic acid is ____ ×…

The specific conductance of $\displaystyle 0.0025$ M acetic acid is $\displaystyle 5 \times 10^{-5} \mathrm{~S} \mathrm{~cm}^{-1}$ at a certain temperature. The dissociation constant of acetic acid is $\displaystyle \_\_\_\_$ $\displaystyle \times 10^{-7}$. (Nearest integer) Consider limiting molar conductivity of $\displaystyle \mathrm{CH}_3 \mathrm{COOH}$ as $\displaystyle 400 \mathrm{~S} \mathrm{~cm}^2 \mathrm{~mol}^{-1}$