5－（4′－氯－2′－羧基苯偶氮）－4－氧代－2－硫代四氢噻唑与铜显色反应的研究

Spectrophotometric Study on the Colour Reaction of Copper with 5-(4′-Chloro-2′-Carboxylphenylazo)-Rhodanine

在弱酸性介质中，铜（Ⅱ）与５－（４′－氯２′－羧基苯偶氮）－４－氧代－２－硫代四氢噻唑在表面活性剂ＴｒｉｔｏｎＸ－１００存在下可以形成一种桔黄色的配合物，最大吸收峰位于４５８ｎｍ，表现摩尔吸光系数ε（４５８）＝９．５×１０４Ｌ·ｍｏｌ（－１）·ｃｍ（－１），配合物中铜与显色剂的摩尔比为１：２。铜浓度在０～２．５μｇ·ｍｌ（－１）范围内符合比耳定律。方法用于合金中铜含量的分析，结果令人满意。

In weak acid solution,copper(Ⅱ)ions can react with5-(4′- chloro2′-car-boxylphenylazo)-rhodanine to forrn an orange complex, which exhibits an absorption maxi-mum at 458nm with a molar absorptivity of 9.5×104L· mol(-1)·cm(-1).The molar ratio ofCu:CCPOST in the complex has been estimated as 1:2.Baeer s law is obeyed in the rangeof 0～2.5μg·ml(-1)for Cu(Ⅱ).It has been used to the determination of Cu(Ⅱ) in alloysamples with satisfactory results.