微热量热法测定斯蒂芬酸碳酰肼盐在DMF中溶解过程的热动力学参数(英文)

Determination of Thermokinetic Parameters in Dissolution Process of DMF of Carbohydrazide Styphnates by Microcalorimetry

用SETARAM C80微热量热仪研究了298.15K时斯蒂芬酸碳酰肼锰([Mn2(CHZ)2(TNR)2(H2O)4]n)、斯蒂芬酸碳酰肼镍([Ni(CHZ)3(TNR)]n)和斯蒂芬酸碳酰肼铅([Pb2(CHZ)2(TNR)2(H2O)2]n)在DMF中的溶解过程、热化学性质及热动力学参数。结果表明,3种配合物在DMF中的溶解过程均为放热反应,但放热峰明显不同,这是由于溶质分子的结构和极性不同而导致的。通过对实验数据的多项式拟合,推导得到三种配合物的溶解焓(ΔsolH)、相对表观摩尔焓(ФLi)、相对偏摩尔焓(Li)和稀释焓(ΔdilH1,2)经验公式,并计算出其标准摩尔溶解焓(ΔsolHθm)分别为-17.75kJ·mol-1,-29.76kJ·mol-1和-15.35kJ·mol-1。由其动力学方程,获得了溶解反应速率常数(k)和反应级数(n)。

The dissolving processes,thermochemical properties and thermokinetic parameters of manganese carbohydrazide styphnate （[Mn2 （CHZ）2（TNR）2（H2O）4]n）,nickel carbohydrazide styphnate （[Ni（CHZ）3（TNR）]n） and lead carbohydrazide styphnate （[Pb2（CHZ）2（TNR）2（H2O）2]n） in N,N-dimethylformamide （DMF） at 298.15 K were studied by a SETARAM C80 calorimeter.The results show that the dissolving process of them in DMF are exothermic,however the exothermic peaks are different.The results are associated with the different molecular structure and polarity of solutes.The empirical formulas for the enthalpies of dissolution （△sol H）,the relative apparent molar enthalpies （ΦLi）,the relative partial molar enthalpies （Li）,and the enthalpies of dilution （△dilH1,2） are respectively deduced by polynomial fitting of experimental data.The standard enthalpies of dissolution （△sol Hθm） are calculated respectively as-17.75 kJ · mol-1,-29.76 kJ · mol-1 and-15.35 kJ · mol-1.The rate constant of dissolution reaction（k）,and the reaction order （n） are obtained from the kinetic formulas.