tetraphosphorus hexoxide

chemical compound

Also known as: phosphorus(III) oxide

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July 14, 2026

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Tetraphosphorus hexoxide, also known as phosphorus trioxide, is a chemical compound with the formula P₄O₆. It is a white, crystalline solid that has a garlic-like odor and emits a poisonous vapor.12

This compound is created by burning phosphorus in a limited supply of air or oxygen. Tetraphosphorus hexoxide reacts with cold water to produce phosphorous acid and decomposes when exposed to hot water. It is considered the acid anhydride of phosphorous acid. When heated, it can oxidize in the air to form phosphorus(V) oxide (P₄O₁₀).12

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oxide
Oxides of phosphorus
…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 solid that smells like garlic and has a poisonous vapour. It oxidizes slowly in air…
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…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 solid that smells like garlic and has a poisonous vapour. It oxidizes slowly in air…
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