Calcium phosphide

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Calcium phosphide
Identifiers
CAS number1305-99-3 YesY
PubChem4337964
Jmol-3D imagesImage 1
Properties
Molecular formulaCa3P2
Molar mass182.18 g/mol
Appearancered-brown crystalline powder or grey lumps
Density2.51 g/cm3
Melting point~1600 °C
Solubility in waterdecomposes
Hazards
R-phrasesR15/29 R28 R50
S-phrases(S1/2) S22 S43 S45 S61
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references
 
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Calcium phosphide
Identifiers
CAS number1305-99-3 YesY
PubChem4337964
Jmol-3D imagesImage 1
Properties
Molecular formulaCa3P2
Molar mass182.18 g/mol
Appearancered-brown crystalline powder or grey lumps
Density2.51 g/cm3
Melting point~1600 °C
Solubility in waterdecomposes
Hazards
R-phrasesR15/29 R28 R50
S-phrases(S1/2) S22 S43 S45 S61
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
Infobox references

Calcium phosphide (CP, Ca3P2) is a chemical is used in incendiary bombs. It has the appearance of red-brown crystalline powder or grey lumps, with melting point of 1600 °C. Its trade name is Photophor for the incendiary use or Polytanol for the use as rodenticide.

It may be formed by reaction of the elements.[citation needed] Metal phosphides have been used as rodenticides. A mixture of food and calcium phosphide is left where the rodents can eat it. The acid in the digestive system of the rodent reacts with the phosphide to generate the toxic gas phosphine. This method of vermin control has possible use in places where rodents immune to many of the common poisons have appeared. Other pesticides similar to calcium phosphide are zinc phosphide and aluminium phosphide.

Calcium phosphide is also used in fireworks, torpedoes, self-igniting naval pyrotechnic flares, and various water-activated ammunition. During the 1920s and 1930s, Charles Kingsford Smith used separate buoyant canisters of calcium carbide and calcium phosphide as naval flares lasting up to ten minutes. It is speculated[according to whom?] that calcium phosphide was an ingredient of some ancient Greek fire formulas.

Calcium phosphide is a common impurity in calcium carbide, which may cause the resulting phosphine-contaminated acetylene to ignite spontaneously.[citation needed]

Safety considerations[edit]

On contact with acids or water, calcium phosphide releases phosphine, which is toxic and can cause explosions in air.

References[edit]