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Red phosphorus may be formed by heating white phosphorus to 300 °C (570 °F) in the absence of air or by exposing white phosphorus to sunlight. Red phosphorus exists as an amorphous network. Upon further heating, the amorphous red phosphorus crystallizes. It has two crystalline forms: violet phosphorus and fibrous red phosphorus. Bulk red ...
Under standard conditions, red phosphorus is more stable than white phosphorus, but less stable than the thermodynamically stable black phosphorus. The standard enthalpy of formation of red phosphorus is −17.6 kJ/mol. [3] Red phosphorus is kinetically most stable. Being polymeric, red phosphorus is insoluble in solvents. It shows ...
In this sense, red phosphorus is not an allotrope, but rather an intermediate phase between the white and violet phosphorus, and most of its properties have a range of values. For example, freshly prepared, bright red phosphorus is highly reactive and ignites at about 300 °C (572 °F), [ 22 ] though it is more stable than white phosphorus ...
White phosphorus, yellow phosphorus, or simply tetraphosphorus (P 4) is an allotrope of phosphorus. It is a translucent waxy solid that quickly yellows in light (due to its photochemical conversion into red phosphorus ), [ 2 ] and impure white phosphorus is for this reason called yellow phosphorus.
Mixes of red, green and blue, or a single white phosphor, can also be encountered. Red: Yttrium oxide-sulfide activated with europium is used as the red phosphor in color CRTs. The development of color TV took a long time due to the search for a red phosphor. The first red emitting rare-earth phosphor, YVO 4:Eu 3+, was introduced by Levine and ...
A U.S.-led military coalition also deployed white phosphorus weapons in Syria and Iraq in its war against ISIS in 2017, according to HRW. Israel, too, previously used the substance during a 2008 ...
The Pentagon recommended providing the white phosphorus shells to Ukraine as part of several aid packages, including a recent one, as a Presidential Drawdown Authority, according to the officials.
Red phosphorus – amorphous polymeric solid; Scarlet phosphorus; Violet phosphorus with monoclinic crystalline structure; Black phosphorus – semiconductor, analogous to graphite; Diphosphorus – gaseous form composed of P 2 molecules, stable between 1200 °C and 2000 °C; created e.g. by dissociation of P 4 molecules of white phosphorus at ...