Aqueous solutions of lithium hydroxide at various temperatures: Conductivity and activity coefficients

The conductivity of LiOH aqueous solutions has been determined at 15, 25, and 45°C. The data analysis showed that LiOH is a slightly associated electrolyte, its association increasing with temperature. The association constant and distance parameter obtained from the conductivity data were successfully employed to calculate the activity coefficients of the solutions. The same procedure applied to very precise conductivity data for NaOH aqueous solutions enabled us to assess the reliability of this method of calculation of activity coefficients up to 0.1m. The alkali metal hydroxides show a reverse trend in the way their properties change with cationic radius, as is the case for the fluorides with which they are compared.