极谱法测定冠醚15C5配合物稳定常数的实验研究

Study on the Stable Constant of 15C5 Complexes with Polargraphy

为了寻找溶剂的性质对冠醚配位化合物稳定性影响的规律性，用极谱法测定了冠醚１５Ｃ５ 在甲醇（ＭｅＯＨ） 和乙腈（ＭｅＣＮ） 、乙醇（ＥｔＯＨ） 和乙腈（ＭｅＣＮ）的混合溶剂中与Ｐｂ２＋ ，Ｃｏ２ ＋ ，Ｎｉ２＋ ，Ｃｕ２＋ 等金属阳离子形成的配合物稳定常数ｌｏｇＫ，并进一步研究了溶剂的性质对配合物稳定性影响的规律性，得出了配合物的稳定常数ｌｏｇ Ｋ与混合溶剂中乙腈的摩尔分数ｘ 的关系．

In order to find the law of the influence of the solvent,polarographic is used to determine the stability constants of complexes of crown ether 15C5 with Pb 2+ ,Co 2+ ,Ni 2+ ,Cu 2+ in MeOH+MeCN,EtOH+MeCN mixtures,and the law of influence of solvent on stable constants is discussed.According to the experiment,the fact that the log K of each of the complexes increases with the increase of MeCN of the mixtures is found.There is a linear relationship between log K and the mole fraction of MeCN.