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 m etal salts MgCl2 MgBr2, Mg(NO3)(2), CaCl2, CaBr2 and Ca(NO3)(2) by which th e ion-solvent interactions are reported in the concentration range in dioxa ne-water mixtures at mass fraction of 0, 3, 10, 20 and 30% at 30 degrees, 3 5 degrees, 40 degrees and 45 degrees C +/- 0.01. The conductance data were analyzed for the limiting molar conductivity, Lam bda(o), by the Fuoss-Edelson conductivity equation for the 2:1 unsymmetrica l electrolytes. The results were discussed in terms of the solute-solvent i nteraction from the temperature coefficient of Walden product, Lambda(o)eta of the electrolyte solutions. Moreover, Lambda(o)eta was found to exhibit a linear relationship with the dielectric constant, epsilon, of the dioxane -water mixtures. The study gives information regarding the ion-solvent inte ractions from the mobilities and Walden product of the ions in the solvent. The ions appear to interact appreciably and the ion-solvent interaction te nds to increase in the order Ca > Mg for the same anion while for the anion s, the trend decreases in the order Cl- < Br- < No-3(-).