Ionic interaction of electrolyte with dilute solution of poly(vinyl alcohol) at different temperatures

Abstract

The ionic interactions of ZnSO4 · 7H2O were studied, using dilute solution of polymer as a solvent. The ionic conductance of ZnSO4 · 7H2O in aqueous and mixed solvent systems of aqueous poly(vinyl alcohol) (0–0.9%) was measured in concentration range (2 × 10−3 to 10 × 10−2 m dm−3) at different temperatures (25–45°C), respectively. Conductance data were analyzed by Ostwald dilution law to get the limiting molar conductance (λm°). The limiting molar conductance () decreased with the increase in the composition of polymer showing decreased ion–solvent interaction. Walden product, degree of dissociation and dissociation constant were also calculated using conductance data. Thermodynamic parameters such as free energy change of activation (ΔG*), enthalpy change of activation (ΔH*) and entropy change of activation (ΔS*) were also calculated at various temperatures as function of concentration of electrolyte in aqueous and mixed solvent systems.