An analytical and kinetic investigation of the vanadium(V)-catalysed bromate oxidation of Bordeaux. Part III. The catalytic determination of vanadium(V)

Abstract

A procedure is described for the determination of vanadium(V) at concentrations of 0·005 to 0·2 µg ml^–1, with a coefficient of variation for the determination of 0·05 µg ml^–1 of 3 per cent. The method depends on catalysis by vanadium of the bromate oxidation of Bordeaux. The most suitable working conditions and calibration technique have been selected on the basis of previously reported kinetic studies of this system.

The interference effects of 37 cations, anions and complexing agents have been investigated and of these ten showed important interference, the most serious being those caused by thiocyanate, nitrite, iodide, ruthenium and copper. Information on the mechanism of the reaction is used to classify the possible sources of interference. The rôles of the interferences encountered experimentally are explained in terms of this classification.