间硝基偶氮氯膦与镨络合物形成反应的分光光度法研究

SPECTROPHOTOMETRIC STUDY ON THE COMPLEX FORMATATION BETEEN PRASEODYMIUM AND CHLOROPHOSPHONAZO-m-NO_2

用分光光度法测定了间硝基偶氮氯膦(CPAmN)的离解常数。研究了镨与间硝基偶氮氯膦配合物α型的形成条件、组成、积累稳定常数以及由α型形成β型配合物条件和有关动力学特征。

The dissociation of chlorophnazo- m- NO2 (CPAmN) in Aqueos solution have been studied spectrophometrically. The Pr-CPAmN complex have two types: α-type and β-type. They have been studied in article, respectively. The composition of α-type Pr-CPAmN complex have been estimated to be 1 : 1, 1 : 2 and 1 : 3. By the method of slope ratio, continuous variation and equilibrium shift. The 1 : 3 complex existing in an excess of reagent is very stable in acidic medium with an overall stability constant lg K of 47. 35. The β-type Pr-CPAmN complex is formed from α-type complex under a certain experimental condition. Kinetic studies indicate that this is a first order reaction. Its half time 9. 33 minutes.