A new relation from the HSAB theory for predicting the conductivity maxima of salts in nonaqueous solvents

Abstract

It is shown that not only the relative permittivity or the dynamic viscosity, but also the chemical nature of the salt and that of the solvent can be taken into account to predict the most important properties of electrolytes: the conductivity maximum κ MAX and the equivalent conductivity at infinite dilution Λ 0. For taking into account the chemical nature of the salt and of the solvent, we assumed that solvation reactions could be expressed in terms of the absolute chemical hardness of the salt, η ACH salt, and that of the solvent, η ACH solvent (or their absolute difference, ∣Δ η ACH∣). Relations are proposed for κ MAX and the equivalent conductivity at infinite dilution Λ 0. Their validity is supported by our own conductivity data and by equivalent conductivity at infinite dilution data from the literature for a wide range of different systems. The accuracy of our predictions seems to be ±20%.