Activity behaviour of electrolyte solutions: Evaluation of temperature effects by means of the quasi-random lattice model

The paper presents some applications of the Moggia–Bianco (quasi-random lattice) model for the calculation of mean activity and osmotic coefficients of electrolyte solutions, with emphasis on temperature effects. Aqueous uni-univalent and uni-divalent electrolytes from 0 °C to 100 °C are considered. Results show that the model is in general applicable over wide ranges of concentrations and temperatures, despite its dependence on a unique fitting parameter (which is, sometimes, experimentally known).Some theoretical aspects of the model are investigated. Hydration diameters are evaluated for uni-univalent systems. Concerning uni-divalent systems, charge-asymmetry effects are accounted for more rigorously than in previous works, starting from a better assessment of the relationship between the behaviour of the electrolyte at very low concentrations and the behaviour occurring at high concentrations.