Transference Numbers for KCl in Ethanol-Water and Dioxane-Water Mixtures at 25 degrees C

Transference numbers were determined by the moving-boundary method for KCl in aqueous mixtures containing 12, 20, 40, 60, and 79 wt.% ethanol, and 22, 44, 62, and 75 wt.% 1,4-dioxane. The boundaries were detected by the potentiometric method using an autogenic cell with a cadmium anode. Little concentration dependence was expected since all the transference numbers were close to 0.5. The Fuoss-Onsager theory for the eleetrophoretic effect was used for extrapolation to infinite dilution. The precision of the measurements appears to be well within 0.05%.