Thermodynamics of aqueous sodium and potassium dihydrogen orthophosphate solutions at 25°C

Abstract

The osmotic coefficients of aqueous NaH₂PO₄ and aqueous KH₂PO₄ over the ranges 1.0-6.5 mol kg^-1 for the sodium salt and 0.85-2.2 mol kg^-1 for the potassium salt were determined at 25°C by the isopiestic method. Our data were combined with the data of Scatchard and Breckenridge for low concentrations in order to calculate smooth values of osmotic and activity coefficients for concentrations down to 0.1 mol kg^-1.