摘要
本文研究了Ｐｂ（Ⅱ）－５－Ｂｒ－ＰＡＤＡＰ及Ｚｎ（Ⅱ）－５－Ｂｒ－ＰＡＤＡＰ络合反应体系的吸收光谱，用基于Ｒｏｓｅｎｂｒｏｃｋ算法的最优化程序处理了光度测量数据，发现Ｐｂ（Ⅱ）与５－Ｂｒ－ＰＡＤＡＰ形成１：１络合物，稳定常数ｌｇβ＿１＝１１．２１，摩尔吸光系数ε＿１＝６．２×１０￣４Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１）；Ｚｎ（Ⅱ）在ｃ＿Ｌ＞ｃ＿Ｍ的条件下主要形成１：２络合物，ｌｇβ＿２＝２２．３６，ε＿２＝１．２８×１０￣５Ｌ·ｍｏｌ￣（－１）·ｃｍ￣（－１）。
The absorption spectra of Pb(Ⅱ )-5-Br-PADAP and Zn(Ⅱ)-5-Br-PADAP complexing systems are studied,and their spectrophotometric data are pro-cessed by using an optimization program based on Rosenbrock's method. It is deter-mined that Pb(Ⅱ)ion forms 1 :1 complex with 5-Br-PADAP,the stability constant lgβ_1 of the complex is 11.21,the molar absorptivity is 6.2×10￣4L·mol￣(-1)·cm￣(-1);Zn(Ⅱ)ion reacts with 5-Br-PADAP and forms 1 :2 complex under the condition of c_L >c_M,the stability constant lgβ_2 is 22.36,the molar absorptivity is 1. 28 × 10￣5L·mol￣(-1)·cm￣(-1)。
出处
《北京大学学报（自然科学版）》
CAS
CSCD
北大核心
1994年第6期655-658,共4页
Acta Scientiarum Naturalium Universitatis Pekinensis
关键词
铅
锌
分光光度法
络合反应
最佳化
lead
zinc
2-( 5-Br-2-pyridylazo)-5-diethylaminophenol
stability con-stant
optimization
spectrophotometry
