phosphorus pentoxide

chemical compound

Also known as: diphosphorus pentoxide, phosphoric anhydride, phosphorus(V) oxide, tetraphosphorus decaoxide(Show More)

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July 23, 2026

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Phosphorus pentoxide, also known as tetraphosphorus decaoxide, is a chemical compound formed by phosphorus and oxygen. It is one of two common oxides of phosphorus, the other being phosphorus(III) oxide.1

Phosphorus pentoxide is a white powder that is very stable and a poor oxidizing agent. It has a strong affinity for water and is used as a drying agent for gases and to remove water from various compounds. When P₄O₁₀ is added to water, it reacts vigorously, producing heat and forming orthophosphoric acid. This reaction is represented by the chemical equation: P₄O₁₀ + 6H₂O → 4H₃PO₄.1

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nitrile
…formed by heating amides with phosphorous pentoxide. They can be reduced to primary amines through the action of lithium aluminum hydride or hydrolyzed to carboxylic acids in the presence of either an acid or a base.
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…formed by heating amides with phosphorous pentoxide. They can be reduced to primary amines through the action of lithium aluminum hydride or hydrolyzed to carboxylic acids in the presence of either an acid or a base.
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amorphous solid
Properties of oxide glasses
…as optical glasses) based on phosphorus pentoxide (P₂O₅) are highly resistant to hydrofluoric acid and act as efficient heat absorbers when iron oxide is added. The table of some typical commercial oxide glasses of the types described gives their compositions and physical properties.
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…as optical glasses) based on phosphorus pentoxide (P₂O₅) are highly resistant to hydrofluoric acid and act as efficient heat absorbers when iron oxide is added. The table of some typical commercial oxide glasses of the types described gives their compositions and physical properties.
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