Transfer chemical potentials for ions, solubilities of salts and kinetics of reactions involving inorganic complex ions at ambient pressure and 298.2 K in binary aqueous mixtures containing ethanol and propan-2-ol

Abstract

Solubilities of several complex salts at ambient temperature and pressure are reported for aqueous solutions and for solutions in binary aqueous organic mixtures. The organic cosolvents are ethanol and propan-2-ol. These and earlier published solubilities are analysed using the TATB assumption which sets the transfer chemical potentials of Ph₄As⁺ ions equal to those of Ph₄B^– ions. The calculations yield transfer parameters for various ions including complex metal ions. Derived transfer parameters for ions are compared for a range of solvent systems comprising binary aqueous mixtures, including those systems where the organic cosolvents are methanol, ethanol, propan-2-ol and acetone. These transfer parameters are used in an analysis of kinetic data describing chemical reaction between hydroxide ions and iron(II) complex cations, [Fe(phen)₃]²⁺ in aqueous solutions. Definitions of standard state chemical potentials for solutes and solvents are considered with reference to descriptions of composition of these systems using the mole fraction scale.