Thermodynamically consistent equations for the accurate description of the dependence on concentration of the properties of electrolyte solutions are proposed, based on a polynomial of order i /4 and a unique set of adjustable coefficients. The equation for the logarithm of the solvent activity ln a 1 ( m ) was derived first, followed by analogous expressions for the osmotic coefficient ϕ ( m ), the solvent activity a 1 ( m ) and activity coefficient γ 1 ( m ) and finally for the mean ionic activity coefficient $$\gamma_{ \pm }^{o} (m)$$ γ ± o ( m ) . The descriptive capability of these equations was verified and favorably compares with the extended Pitzer equation. Finally, it was demonstrated that the evaluation of $$\ln \gamma_{ \pm }^{o} (m)$$ ln γ ± o ( m ) is strongly influenced by the fitting capability of the expression used in the correlation of ϕ ( m ) in the low molality region.

中文翻译：

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用于精确描述具有一组独特参数的电解质溶液的溶剂活性和相关特性的对数的热力学一致方程：平均活性系数评估的关键分析

基于 i / 4 阶多项式和一组独特的可调系数，提出了用于准确描述电解质溶液性质对浓度的依赖性的热力学一致方程。首先推导出溶剂活度ln a 1 ( m )的对数方程，然后推导出渗透系数φ ( m )、溶剂活度a 1 ( m )和活度系数γ 1 ( m )的类似表达式，最后对于平均离子活度系数 $$\gamma_{ \pm }^{o} (m)$$ γ ± o ( m ) 。验证了这些方程的描述能力，并与扩展的 Pitzer 方程进行了比较。最后，