Reactions of liquid sodium with transition-metal oxides

Vanadium pentoxide is reduced by liquid sodium to the oxide V2O3 and sodium oxide at low temperatures (150 °C). On increasing the temperature (up to 600 °C) the ternary oxides Na4VO4 and NaVO2 are produced. Vanadium dioxide reacts at 150 °C to form the oxide NaVO2 which is stable to liquid sodium up to 600 °C. Vanadium(III) oxide, V2O3, reacts with liquid sodium to give a mixture of the ternary oxide, NaVO2, and the monoxide, VO; the latter oxide is stable to pure liquid sodium up to 600 °C but may be oxidised by solutions of oxygen in liquid sodium to NaVO2 which may be further oxidised by oxygen in sodium to Na4VO4.