Etude des mobilités ioniques dans les mélanges eau–hexaméthylphosphotriamide (HMPT) à 25 °C. II. Application de la théorie de Zwanzig au comportement des ions monovalents

The electrical conductibilities of 19 1-1 MX electrolytes (M = alkaline, quaternary ammonium; X = perchlorate, halide, nitrate) in water–hexamethylphosphotriamide mixtures at 25 °C has been measured. The individual conductibilities of 17 monovalent ions in these mixtures were calculated using the hypothesis of ion equimobility in Bu4NBPh4. Following a critical review of the traditionally used methods, it has been shown that, from these results, Zwanzig's theory alone allows the objective assessment of ion–solvent interactions. However, this theory at its present state of development cannot be used to elucidate all the problems (because Zwanzig considers the displacement of the free ion) but it does distinguish the nature of the interactions between an ion and the solvent, depending on the mobility of that ion.