phosphorus oxide

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June 17, 2026

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Phosphorus oxides are compounds formed between phosphorus and oxygen. The two most common are phosphorus(III) oxide (P₄O₆), also known as phosphorus trioxide, and phosphorus(V) oxide (P₄O₁₀), also known as phosphorus pentoxide.1

Phosphorus trioxide is a white, volatile, crystalline compound that is made by burning phosphorus in a limited supply of air or oxygen. It reacts with cold water to form phosphorous acid.2

Phosphorus pentoxide is a white powder that is very stable. It is the acid anhydride of phosphoric acid and is used extensively as a drying agent due to its strong affinity for water.1

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oxide
Oxides of phosphorus
Phosphorus forms two common oxides, phosphorus(III) oxide (or tetraphosphorus hexoxide), P₄O₆, and phosphorus(V) oxide (or tetraphosphorus decaoxide), P₄O₁₀. Both oxides have a structure based on the tetrahedral structure of elemental white phosphorus. Phosphorus(III) oxide is a white crystalline
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Phosphorus forms two common oxides, phosphorus(III) oxide (or tetraphosphorus hexoxide), P₄O₆, and phosphorus(V) oxide (or tetraphosphorus decaoxide), P₄O₁₀. Both oxides have a structure based on the tetrahedral structure of elemental white phosphorus. Phosphorus(III) oxide is a white crystalline
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