# Suggest a way to determine the

Question:

Suggest a way to determine the $\Lambda_{m}^{0}$ value of water.

Solution:

Applying Kohlrausch's law of independent migration of ions, the $\Lambda_{m}^{0}$ value of water can be determined as follows:

$\Lambda_{m\left(\mathrm{H}_{2} \mathrm{O}\right)}^{0}=\lambda_{\mathrm{H}^{+}}^{0}+\lambda_{\mathrm{OH}^{-}}^{0}$

$=\left(\lambda_{\mathrm{H}^{+}}^{0}+\lambda_{\mathrm{Cr}}^{0}\right)+\left(\lambda_{\mathrm{Na}^{+}}^{0}+\lambda_{\mathrm{OH}^{-}}^{0}\right)-\left(\lambda_{\mathrm{Na}^{+}}^{0}+\lambda_{\mathrm{CI}}^{0}\right)$

$\Lambda_{m(\mathrm{HCl})}^{0}+\Lambda_{m(\mathrm{NaOH})}^{0}-\Lambda_{m(\mathrm{NaCl})}^{0}$

Hence, by knowing the $\Lambda_{m}^{0}$ values of $\mathrm{HCl}, \mathrm{NaOH}$, and $\mathrm{NaCl}$, the $\Lambda_{m}^{0}$ value of water can be determined.