Solubility and activity coefficient of thallium(I) chloride in aqueous solutions: TlCl–HCl–H2O and TlCl–NaCl–H2O at 298.15 K

Abstract

The solubility of thallium(I) chloride has been measured in aqueous solutions of hydrochloric acid and sodium chloride at concentrations ranging from 0.005 to 4.0 mol kg^–1. The data were fitted to Pitzer's equations using a procedure which allowed the single electrolyte parameters, β⁰, β¹ and C^ϕ for TlCl to be evaluated together with the relevant mixture parameters. Consideration of the higher-order limiting law for symmetrical mixing in the form proposed by Pitzer did not give an improved fit of the experimental data. The β¹ term can adequately describe the intermediate type of weak electrolyte behaviour shown by TlCl without the need to assume ion association explicitly.