Ion-Solvent Interaction of Biunivalent Electrolytes in Dioxane-Water Mixtures from Conductivity Data at Different Temperatures

This paper presents the conductivity measurements for some alkaline earth metal salts MgCl2, MgBr2, Mg(NO3)2, CaCl2, CaBr2 and Ca(NO3)2 by which the ion‐solvent interactions are reported in the concentration range in dioxane‐water mixtures at mass fraction of 0, 3, 10, 20 and 30% at 30°, 35°, 40° and 45°C ± 0.01. The conductance data were analyzed for the limiting molar conductivity, Ao, by the Fuoss‐Edelson conductivity equation for the 2:1 unsymmetrical electrolytes. The results were discussed in terms of the solute‐solvent interaction from the temperature coefficient of Walden product, Λoη of the electrolyte solutions. Moreover, Λoη was found to exhibit a linear relationship with the dielectric constant, ϵ, of the dioxane‐water mixtures. The study gives information regarding the ion‐solvent interactions from the mobilities and Walden product of the ions in the solvent. The ions appear to interact appreciably and the ion‐solvent interaction tends to increase in the order Ca > Mg for the same anion while for the anions, the trend decreases in the order Cl− < Br− < No−3.