Thermodynamics Research Center / ThermoML | Fluid Phase Equilibria

ABSTRACT

Molar conductance of lithium acetate, sodium acetate and potassium acetate were studied in aqueous 2-butanol solutions with an alcohol mass fraction of 0.70, 0.80 and 0.90 at 298.15, 303.15 and 308.15 K. The conductance data were analyzed with the Fuoss conductance concentration equation to evaluate the limiting molar conductances, association constants and cosphere diameter for ion-pair formation. Gibbs energy, enthalpy and entropy for ion-association reaction were derived from the temperature dependence of association constant. Activation energy for ionic movement was derived from the temperature dependence of the limiting molar conductance. Based on the composition dependence of Walden products and different thermodynamic properties Gibbs energy, enthalpy and entropy for ion-association reaction and the activation energy for ionic movement, the influence of the solvent composition on ion-association and solvation behavior of ions were discussed in terms of ion-solvent, ion-ion interactions and the structural changes in the mixed solvent media.