Spectrophotometric Determination of Copper(II) in Soil in the Form of a Pyrogallol Red Complex in the Presence of Surfactants

A spectrophotometric procedure for the quantitative determination of copper(II) by a reaction of complex formation with pyrogallol red in the presence of cationic and nonionic surfactants is proposed. The optimum conditions for the analysis are determined. The procedure is tested for the determination of copper(II) in a sample of a soil extract. The following metrological characteristics of the proposed procedure are assessed: the limit of detection is 0.12 mg/kg of soil and the relative standard deviation is <0.05.