What is "vanadate"

Vanadate \Van"a*date\, n. [Cf. F. vanadate.] (Chem.) A salt of vanadic acid. [Formerly also vanadiate.]

n. 1 (context chemistry English) any salt of vanadic acid 2 (context chemistry English) any of the corresponding anions, VO₃, VO₄, or V₂O₇

n. a salt or ester of vanadic acid; an anion containing pentavalent vanadium

In chemistry, a vanadate is a compound containing an oxoanion of vanadium generally in its highest oxidation state of +5. The simplest vanadate ion is the tetrahedral, orthovanadate, anion, which is present in e.g. sodium orthovanadate and in solutions of VO in strong base ( pH > 13 ). Conventionally this ion is represented with a single double bond, however this is a resonance form as the ion is a regular tetrahedron with four equivalent oxygen atoms.

Additionally a range of polyoxovanadate ions exist which include discrete ions and "infinite" polymeric ions. There are also vanadates, such as rhodium vanadate, RhVO, which has a statistical rutile structure where the Rh and V ions randomly occupy the Ti positions in the rutile lattice, that do not contain a lattice of cations and balancing vanadate anions but are mixed oxides.

In chemical nomenclature when vanadate forms part of the name, it indicates that the compound contains an anion with a central vanadium atom, e.g. ammonium hexafluorovanadate is a common name for the compound (NH)VF with the IUPAC name of ammonium hexafluoridovanadate(III).