摘要：

在pH8.0的硼砂-硼酸缓冲溶液中，在非离子表面活性剂OP存在下，锌(Ⅱ)与5-Br-PADAP生成红色络合物，络合物的最大吸收波长为555nm，表观摩尔吸光系数ε=1.44×105L/(mol.cm)。测得络合物组成比为n〔(Zn(Ⅱ)〕n∶(5-Br-PADAP)=1∶2，锌质量浓度在0-0.6mg/L符合比尔定律。加入掩蔽剂后用该方法测定环境水中微量锌，结果满意。

关键词: 锌, 环境水, 分光光度法

Abstract:

A red complex of zinc (Ⅱ) with 2-[(5-bromo-2-pyridyl)-azo]-5-diethyl-aminophenol(5-BrPADAP) is formed in the mediumofNa₂B₄O₇-H₃BO₃(pH 8.0)buffer solution containing OP. The maximumabsorption of complex is at 555 nm and its apparent molar absorptivity is 1.44×10⁵ L/(mol·cm).The molar ratio of Zn (Ⅱ) to 5-Br-PADAP in the complex is 1 ∶2. The Beer’s lawis obeyed in the concentration range of 0~0.6 mg/L for zinc (Ⅱ). The trace zinc can be determined directly in environmental water by adding masking agents and the results are satisfactory.

Key words: zinc, environmental water, spectrophotometry

中图分类号: 

• X832