Acid decomposition of decavanadate: specific salt effects

Abstract

The reaction of decavanadate(V), V₁₀O₂₈^6–, and also the reduced decavanadate V^IV₇V^V₃O₂₈^13–, with acid in the presence of a number of supporting electrolytes has been studied. Large cations such as tetra-alkylammonium ions and trialkylsulphonium ions markedly decrease the rate of reaction. This is shown to be due to the formation of stable ion pairs with decavanadate which do not react with acid. The effect is greater the larger the size of the onium ion. Such ion pairs do not form with the alkali-metal cations.