Influence of solvent polarity upon salt solubilities, III: Solubilities of KCl in water/tetrahydrofuran at 25°C

Solubility of Sodium Halides in Aqueous Mixtures with ε-Increasing Cosolvents: Formamide, N-Methylformamide, and N-Methylacetamide at 298.15 K

“…Therefore, it is not easy to find an equation unequivocally describing the solubility as a function of all of these parameters. Many authors have tried to deduce an equation that considers all of these aspects at the same time (see, for example, refs , , , , – , , , and ), almost always on the theoretical basis of the model of Born. , …”

“…The immense majority of experimental studies on the solubility of salts have been carried out in water, , pure organic solvents, or aqueous–organic mixtures with cosolvents that have a dielectric constant lower than that of water (ε-decreasing system). Among the systems of this kind, the most studied are those containing alcohols − ,− ,− and ketones, esters and ethers, among other chemical compounds. ,,,,− Data on systems with cosolvents with dielectric constants greater than the dielectric constant of pure water (ε-increasing system) are somewhat more scarce and usually include some amides as the cosolvent. − Aqueous mixtures containing amides (in particular, cyclic amides) constitute an essential tool in the understanding of the behavior of complex molecules of biological interest. , Extensive work has been published on water–amide systems to discover the mode in which water exercises kinetic and thermodynamic control of the chemical activities of polypeptides. The unusually high density of hydrogen bonds in water (strongly self-associated) and the character of the acceptor–donor (−CO–NH–peptide bond) make these water–amide systems very interesting from a structural point of view.…”