Phosphorus tetroxide
Diphosphorus tetroxide, or phosphorus tetroxide is an inorganic compound of phosphorus and oxygen. It has the empirical chemical formula. Solid phosphorus tetroxide consists of variable mixtures of the mixed-valence oxides P4O7, P4O8 and P4O9.Preparation
Phosphorus tetroxide is obtainable by thermal decomposition of phosphorus trioxide, which disproportionates above 210 °C to form phosphorus tetroxide, with elemental phosphorus as a byproduct:
In addition, phosphorus trioxide can be converted into phosphorus tetroxide by controlled oxidation with oxygen in carbon tetrachloride solution.
Careful reduction of phosphorus pentoxide with red phosphorus at 450-525 °C also produces the phosphorus tetroxide.
