A study of the chemistry of the polyvanadates using salt cryoscopy

Article abstract of DOI:10.1021/ic50011a015

Glauber's salt cryoscopy and pH measurements have been made on sodium vanadate solutions in the pH range 2.5 to 7. Vanadium was found to exist in neutral solutions as a tetramer of VO₃^-. At lower pH values, confirmation was found for the equilibria V₁₀O₂₈^-6 ?^H+ HV₁₀O₂₈^-5 ?^H+ H₂V₁₀O₂₈^-6 ?^H+ VO₂⁺ No evidence was found for a hexavanadate in the pH range studied. The formation of a heteropolyanion between vanadium and phosphorus was indicated. The heteropolyanion forms from H₂V₁₀O₂₈^-4, but not from the other anionic polyvanadates.