white phosphorus

chemistry

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July 23, 2026

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White phosphorus is an allotropic form of the element phosphorus. It is a soft, waxy solid that glows in the dark and is also known as yellow phosphorus. White phosphorus is highly reactive, toxic, and ignites spontaneously in air at relatively low temperatures, requiring storage under water.123

It has a melting point of 44.1 °C (111.4 °F) and a boiling point of 280 °C (536 °F). Historically, it was discovered by alchemists and later found to be a component of bones. Commercially, phosphorus is primarily produced from phosphate rock and used in fertilizers.1

While elemental phosphorus has some industrial uses, such as in fireworks and matches, most phosphorus is utilized in compound forms, particularly phosphates, which are crucial for life as components of DNA and energy-carrying molecules like ATP.1

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chemical industry
Phosphorus
White phosphorus is used in rodent poison and by the military for smoke generation. Red phosphorus, comparatively harmless, is used in matches. Ferrophosphorus, a combination of phosphorus with iron, is used as an ingredient in high-strength low-alloy steel. In addition, the many organic compounds of…
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White phosphorus is used in rodent poison and by the military for smoke generation. Red phosphorus, comparatively harmless, is used in matches. Ferrophosphorus, a combination of phosphorus with iron, is used as an ingredient in high-strength low-alloy steel. In addition, the many organic compounds of…
Read More

match
…safety matches became widely accepted, white phosphorus matches continued to be popular because of their keeping qualities and resistance to climatic conditions. However, at the end of the 19th century serious toxic effects of white phosphorus (“phossy jaw”) were discovered in the factory workers who made such matches. Phosphorus sesquisulfide,…
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…safety matches became widely accepted, white phosphorus matches continued to be popular because of their keeping qualities and resistance to climatic conditions. However, at the end of the 19th century serious toxic effects of white phosphorus (“phossy jaw”) were discovered in the factory workers who made such matches. Phosphorus sesquisulfide,…
Read More

phosphorus
Properties and reactions
…the three major allotropes are white, red, and black. Phosphorus molecules of formula P₂, structurally analogous to N₂ molecules and evidently also triply bonded, exist only at very high temperatures. These P₂ molecules do not persist at lower temperatures—below about 1,200 °C (2,200 °F)—because of the fact that three single…
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…the three major allotropes are white, red, and black. Phosphorus molecules of formula P₂, structurally analogous to N₂ molecules and evidently also triply bonded, exist only at very high temperatures. These P₂ molecules do not persist at lower temperatures—below about 1,200 °C (2,200 °F)—because of the fact that three single…
Read More