【摘要】 本文用分光光度法测定了显色剂5-（4-磺基-1-萘偶氮）-8-羟基喹啉离解常数，并研究了该显色剂与Yb的络合情况．结果表明：在pH为2－12之间，该显色剂共有三种存在形式：H2L（NH＋）、HL-、L2-，它的离解常数为Ka1＝1.61×10-5，Ka2＝4．10×10-9.在pH＝9．60附近，该显色剂可与Yb3＋形成3：1、2：1、1：1的配合物．更多还原

【Abstract】 A Spectrophotometric method has been used to study the constant of dissociation on 5-(4-sulfo-1-naphthy lazo)-8-hydroxy quinoline and its chromogenic reaction with Ytterbium at pH = 2-12. In the experimental conditions, the chromogenic reagent has three shapes: H2L(NH- ) , HL-, L2-, its constant of dissociation is: Ka1 =1. 61 X 10-5, Ka2 =4. 1 X 10-9. At pH= 9. 6 nearby, it reacts with Ytterbium to form 3: 1, 2: 1, 1: 1 complex.更多还原