盐在混合溶剂中的行为——优先溶剂化数的研究

<正> 引言众所周知,盐溶于液体中时,必然伴随着溶剂化过程的进行。即溶剂分子通过它们和盐离子的相互作用,聚集在离子周围的过程。这些聚集于离子周围的溶剂分子叫溶剂化分子。并且我们知道,这些溶剂化分子又分为:完全介电饱和的最靠近离子的第一层,叫原溶剂化(primary solvation)或化学溶剂化。这层的溶剂化分子数不受温度变化的影响;第一层以外的溶剂化分子叫二级溶剂化(secondary solvation)或物理溶剂化,这一层的溶剂化分子数随着温度的变化而变化,不是固定的。

The Behavior of Salts in Mixed Solvents-Investigation of the Preferention solvation number

Ionic solvation is one of the basic subjects in the solution theory.Althrough there are vast papers on ionic hydration in aquous, but the ionic solvation in non-aquous or mixed solvents are rare, except for the solvation in methnol.According to S. Ohe's suggestion, the results reported here, present the numbers of preferential solvation of KI. KBr in benzene-methanol systerm, LiCl in benzene-ethanol, and 1,2-dichloroethane-ethanol Systerm, and NaI in benzene-ethanol systerm both calculated from the measurement of the salt effect on vapor-liquid equilibrium. Literature data of ZnCl_2 in benzene-ethanol systerm also taken to obtain the number of preferential solvation. In the discussion, the "dielectric effect", "penetrating effect" and "molecular cluster" are used to illustrate the experiment results.