Activity coefficients and solubilities of the system (Ag/Cs)NO3-H2O from vapour pressure measurements

Vapour pressures of water over (Ag/Cs)NO₃-H₂O (0, 40, 60, and 100% AgNO₃) are reported at three temperatures: 152,179, and 218 °C. The water activities derived from these data are fitted with equations for multicomponent electrolyte solutions developed by Van Laar and Pitzer (three models: Van Laar model, Pitzer-Van Laar model, Pitzer-Simonson model). With these models the mean activity coefficients of the salts and the solubilities of the pure salt components (AgNO₃ or CsNO₃) in the ternary mixture are calculated. The advantages of the Pitzer-Simonson model are underlined.