Kinetic Spectrophotometric Determination of Trace Copper(II) with Chlorophosphonazo-I

In HAc-NaAc medium and in the presence of α,α'-bipyidine as an activating agent,a kinetic spectrophotometric method for the determination of trace copper(Ⅱ) has been established,based on its catalytic effect on the reduction of Chlorophosphonazo-I by ascorbic acid.The optimum condition has been studied systematically.The reaction exhibits maximum absorption at 540 nm;the detection limit is 7.1×10-10 g·mL-1;the linear range is 0～0.35 μg/25 mL.The method was applied to determine the tap water and tea samples with satisfactory results.