The average P-P bond length is 2.183(5) Å. The β form of white phosphorus contains three slightly different PĤ molecules, i.e. These forms differ in terms of the relative orientations of the constituent P 4 tetrahedra. It is more common, has cubic crystal structure and at 195.2 K (−78.0 ☌), it transforms into β-form, which has hexagonal crystal structure. At room temperature, the α-form is stable. White phosphorus exists in two crystalline forms: α (alpha) and β (beta). This has been illustrated by calculations of the magnetically induced currents, which sum up to 29 nA/T, much more than in the archetypical aromatic molecule benzene (11 nA/T). The nature of bonding in this PĤ tetrahedron can be described by spherical aromaticity or cluster bonding, that is the electrons are highly delocalized. This PĤ tetrahedron is also present in liquid and gaseous phosphorus up to the temperature of 800 ☌ (1,470 ☏) when it starts decomposing to PĤ molecule in the gas phase has a P-P bond length of r g = 2.1994(3) Å as was determined by gas electron diffraction. It is a soft, waxy solid which consists of tetrahedral PĤ molecules, in which each atom is bound to the other three atoms by a formal single bond. įrom the perspective of applications and chemical literature, the most important form of elemental phosphorus is white phosphorus, often abbreviated as WP. The two most common allotropes are white phosphorus and red phosphorus. Phosphorus has several allotropes that exhibit strikingly diverse properties. Other applications include organophosphorus compounds in detergents, pesticides, and nerve agents.Ĭharacteristics Allotropes Phosphate is needed to replace the phosphorus that plants remove from the soil, and its annual demand is rising nearly twice as fast as the growth of the human population. The vast majority of phosphorus compounds mined are consumed as fertilisers. Low phosphate levels are an important limit to growth in a number of plant ecosystems. Phosphate mines contain fossils because phosphate is present in the fossilized deposits of animal remains and excreta. Elemental phosphorus was first isolated from human urine, and bone ash was an important early phosphate source. Phosphates are a component of DNA, RNA, ATP, and phospholipids, complex compounds fundamental to cells. Phosphorus is an element essential to sustaining life largely through phosphates, compounds containing the phosphate ion, PO 4 3−. Phosphorus is classified as a pnictogen, together with nitrogen, arsenic, antimony, bismuth, and moscovium. The glow of phosphorus is caused by oxidation of the white (but not red) phosphorus-a process now called chemiluminescence. The term phosphorescence, meaning glow after illumination, derives from this property of phosphorus, although the word has since been used for a different physical process that produces a glow. White phosphorus emits a faint glow when exposed to oxygen-hence the name, taken from Greek mythology, Φωσφόρος meaning 'light-bearer' (Latin Lucifer), referring to the " Morning Star", the planet Venus. In white phosphorus, phosphorus atoms are arranged in groups of 4, written as P 4. In minerals, phosphorus generally occurs as phosphate.Įlemental phosphorus was first isolated as white phosphorus in 1669. It has a concentration in the Earth's crust of about one gram per kilogram (compare copper at about 0.06 grams). Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Earth. Phosphorus is a chemical element it has symbol P and atomic number 15.
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