Solvent effects on the thermodynamics of transfer of tris [hydroxymethyl] aminomethane in water-2-ethoxyethanol-mixtures

The solubilities of the base tris [hydroxymethyl] aminomethane have been measured in water-2-ethoxyethanol [ECS] mixtures containing from 0-80 wt.% of ECS as a function of temperature. The usual associated thermodynamic functions were calculated from the results. The effect of added solvent on the st and ard Gibbs energies of base transfer, delta Gt[B] was compared with that of other aqueous organic solvent systems, for which comparable data were available. The solvent effects have been discussed in terms of the st and ard Gibbs energy of base transfer [B] from water to the mixed solvent, delta Gt[B], and the relative values of the st and ard Gibbs energies of HCl transfer, delta Gt[HCl] and of B.HCl, delta Gt[B.HCl] in this solvent system