The persulphate-α,α'-dipyridyl system as indicator in the argentometric controlled-current potentiometric titrations

Abstract

Starting from the voltammetric and controlled-current potentiometric study of the system persulphae-α,α'-dipyndyl in the presence and absence of silver(I), the same system was applied as indicator in the argentometric controlled-current potentiometric titrations of chloride, bromide, iodide, and thiocyanate. The possibility of using either one or two polarized platinum indicator electrodes was studied. The amounts of 0.6-6 mg of bromide, 0.1-10 mg of iodide, 4 mg thiocyanate and 2.6 mg of chloride were determined with relative standard deviations in the range from 0.2 to 1.1%. In general, the results show good agreement with those obtained by a comparative method.