Activity coefficients for the system HBr + CaBr2+ H2O at 298.15 K

Activity coefficients for hydrobromic acid in admixture with calcium bromide in aqueous solutions of constant total ionic strengths I= 0.1, 0.5, 1.0, 1.5 and 2.0 mol kg–1 have been determined at 298.15 K using electromotive force measurements employing hydrogen and silver–silver bromide electrodes. The data have been analysed using Pitzer's equations and Scatchard's neutral electrolyte treatment. A significantly improved analysis with Pitzer's equations was obtained by incorporating his treatment of the effects of higher-order electrostatic terms on the H+–Ca2+ interactions.