应用流动式等温精密微量热技术测定4个温度(293.15、303.15、308.15和318.15 K)下D-山梨醇在纯水和卤化钠水溶液中的稀释焓.根据改进的McMillan-Mayer理论对所测数据进行关联,得到了表观摩尔稀释焓对浓度变化的经验方程和各阶焓相互作用系数(h2,h3和h4)和二阶熵相互作用系数(s2),根据溶质-溶质、溶质-溶剂等弱相互作用对二阶焓、熵及吉布斯自由能相互作用系数进行了讨论,并探讨了温度对稀释焓的影响.结果表明,在山梨醇的纯水溶液和卤化钠水溶液中,其二阶焓相互作用系数h2随温度的升高而逐渐增大;不同温度下的二阶焓相互作用系数与温度成线性关系,因而二阶熵相互作用系数在实验温度范围内为一常量.%The enthalpies of dilution of D-sorbitol in water and sodium halide aqueous solutions had been determined by isothermal flow-mix microcalorimetry at 293. 15K, 303.15K, 308.15K, and 318. 15K. Experiential equations of apparent enthalpies of dilution varying with the concentration of D-sorbitol had been established from the experimental data in terms of the improved McMillan-Mayer theory, and enthalpic interaction coefficients (h2, h3, and h4 ), pairwise entropic interaction coefficient s2 and pairwise Gibbs free energy interaction coefficient g2 obtained. The values of h2 had been discussed in the light of solute-solute and solute-solvent interactions. The results indicated that,the values of h2 increased as raising temperature in pure water and the sodium halide aqueous solutions; and it shows quite well linear dependence on temperature, so s2 is a constant in the experimental range of temperature.
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