Isopiestic Osmotic Coefficients of Tetra-n-methylammonium Chloride with Guanidinium Salts at 298.15 K

Isopiestic osmotic coefficients are presented for aqueous mixtures of tetra-n-methylammonium chloride, (CH₃)₄NCl, with guanidinium salts such as GnCl, CH₃COOGn, GnNO₃, GnClO₄ and Gn₂SO₄ at 298.15 K up to an ionic strength of 2 mol?kg^?1. The osmotic coefficients are analyzed in terms of the Scatchard-Rush-Johnson equations. The activity coefficients of each electrolyte in the mixtures were calculated and fitted by the Harned-type equations. The molar excess Gibbs energy of mixing, Δ_m G ^E, of the mixtures were analyzed with Friedman’s equations.