Thermodynamic studies of (RbF + RbCl + H2O) and (CsF + CsCl + H2O) ternary systems from potentiometric measurements at T=298.2 K

Thermodynamic properties of (RbF + RbCl + H2O) and (CsF + CsCl + H2O) systems were determined by the potentiometric method for different ionic strength fractions y(B) of RbCl/CsCl at 298.2 K. The Pitzer model and the Harned rule were used to fit the experimental values. The Pitzer mixing parameters and the Harned coefficients were evaluated. In addition, the mean ionic activity coefficients of RbF/CsF and RbCl/CsCl, the osmotic coefficients, and the excess Gibbs energies of the systems studied were calculated. (C) 2016 Elsevier Ltd.