Thermodynamic properties of multicomponent NaCl–LiCl–H2O aqueous solutions at temperature 298.15 K

The mixed aqueous electrolytes system of sodium and lithium chlorides has been studied by the hygrometric method at 298.15 K. The relative humidities of this system are measured at the total molalities from 0.3 mol kg−1 to about saturation for different ionic-strength fractions y of NaCl with y = 0.33 , 0.50 and 0.67. The results allow the deduction of water activities and osmotic coefficients. The experimental results are compared with the predictions of the Zdanovskii–Stokes–Robinson (ZSR), the Kusik and Meissner (KM), Robinson and Stokes (RS), Lietzke and Stoughton (LSII), Reilly, Wood and Robinson (RWR), and Pitzer models. From these measurements, the Pitzer mixing ionic parameters are determined and used to predict the solute activity coefficients in the mixture for different ionic-strength fractions of NaCl. The excess Gibbs energy is also determined.