Kinetic enthalpimetric determination of vanadium(V) by its catalytic effect on the oxidation rate of Pyrogallol Red by potassium bromate

Abstract

The V^V-catalysed oxidation of Pyrogallol Red by BrO₃^– was monitored enthalpimetrically. The rate of the reaction was determined graphically from the initial linear slope of the temperature–time curve recorded and was found to be proportional to the V^V concentration over the range 10–150 ng ml^–1. The relative standard deviation obtained for the determination of a 100 ng ml^–1 concentration of the analyte was 6%. Foreign species did not interfere at concentrations as high as 20 µg ml^–1. The method was applied to the determination of V^V in steel with good results.