竞争型三元配合物生成热的量热测定 镍(Ⅱ)-草酸-甘氨酸三元体系

CALORIMETRIC DETERMINATION OF THE HEAT OF FORMATION OF COMPETITIVE TERNARY COMPLEX COMPOUNDS

我们曾经报导过铜（Ⅱ）-草酸-乙二胺三元竞争体系的量热研究。由于铜（Ⅱ）离子的配位数为4。对两个二齿配体（草酸和乙二胺）来说,混配络合物只有一种（MAB）。然而对于（钅臭）（Ⅱ）-草酸-甘氨酸的三元体系来说,情况就较复杂。有三种混配络合物（MAB,MA2B,MAB2）的生成反应必须考虑,所以在热效应计算上就更加复杂,至今尚无文献报道。本文试图建立一种合理的数据处理方法以计算这样复杂体系的热效应。

By utilizing the formation constants of Ni(Ⅱ)-Glycine binary complex compounds and the corresponding heats of formation from literature as well as the formation constants of Ni(Ⅱ)-Oxalate binary complex compounds and the corresponding heats of formation incorporating with the formation constants of Ni(Ⅱ)-Oxalate-Glycine competitive ternary complex compounds determined in our laboratory, the heats of formation of Ni(Ⅱ)-Oxalate-Glycine competitive ternary complex compounds have been determined at 25℃, I=0.1 mol. dm^(-3)(KNO_3)in aqueous solution by means of RD-1 model automatic conduction calorimeter. The results obtained are: △H_(AB)~M=-14.3±2.0kJ·mol^(-1) △H_(A2B)~M=-27.0±2.0kJ·mol^(-1) △H_(AB2)~M=-40.2±2.0kJ·mol^(-1)