V2(SO4)3 + H2SO4 + 8H2O → 2{H[V(SO4)2]•4H2O}
Vanadium(III) sulfate react with sulfuric acid and water to produce tetrahydrate hydrogen disulfatovanadate(III). Sulfuric acid - concentrated solution. This reaction slowly takes place in the ethanol, at a temperature near 0°C.