A water-soluble chromogenic reagent, N,N'-oxalylbis(2-pyridyl-3'-sulphobenzoylhydrazone) has been synthesized. Spectrophotometric and first-and second-derivative spectrophotometric methods for the determination of copper with the reagent have been dev...
A water-soluble chromogenic reagent, N,N'-oxalylbis(2-pyridyl-3'-sulphobenzoylhydrazone) has been synthesized. Spectrophotometric and first-and second-derivative spectrophotometric methods for the determination of copper with the reagent have been developed. Determination has been performed by measuring the absorbance and the first-and second-derivative values of the copper complexes in aqueous solutions (pH 1.89) at 379, 395, 363 and 421 nm, respectively. The method allows the determination of 0.12-1.20 ${\mu}g$ /ml of copper and has been applied to the analysis of aluminium alloy samples. The best results have been obtained from the measurements of the second-derivative values at 421 nm.