$D_{AB}^0=\frac{RT[(\frac{1}{n_{+}})+(\frac{1}{n_{-}})]}{F^2[(\frac{1}{{}_{+}^0})+(\frac{1}{{}_{-}^0})]}$

where

$D_{AB}^0=$ diffusivity $at$ infinite dilute solution, based $on$ molecular

concentration, $c\frac{m^2}{s}$

$R=$ gas constant, $8\mathrm{.}314\frac{J}{m}ol*K$

$=$ temperature, $K$

$T=limiting(zero$ concentration$)$ ionic conductances,

$(\frac{A}{c}{m}^2)(\frac{V}{c}m)(g-$ equiv $\frac{?}{c{m}^3})$

$n_{+},n_{-}=$valences $of$ cation and anion, respectively

$F=$ Faraday's constant $=96,500\frac{C}{g}-$equiv

Table $1\mathrm{.}4$ Limiting Ionic Conductances in Water at $298$

Units: g$-$equiv