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Red phosphorus. 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 ...
Fibrous red phosphorus is another crystalline form of red phosphorus. [7] It is obtained along with violet phosphorus when red phosphorus is sublimed in vacuum in the presence of iodine. [21] It is structurally similar to violet phosphorus. However, in fibrous red phosphorus, phosphorus chains lie parallel instead of orthogonal, unlike violet ...
Phosphorus is a chemical element; it has symbol P and atomic number 15. 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.
White phosphorus forms molecular crystals composed of tetrahedral P 4 molecules. [32] Heating at ambient pressure to 250 °C or exposing to sunlight converts white phosphorus to red phosphorus where the P 4 tetrahedra are no longer isolated, but connected by covalent bonds into polymer-like chains. [33]
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 Palilla as a primary color in television in 1964. [29] In single crystal form, it was used as an excellent polarizer and laser material. [30]
Lead heptaphosphide crystallises in the monoclinic crystal system, with space group P2 1 /c, a=970.70(11), b=673.34(10), c=1243.89(18) pm and β=122.55(1)°. Each phosphorus atom in the phosphorus cluster is connected to the other six.
Hypophosphoric acid can be prepared by the reaction of red phosphorus with sodium chlorite at room temperature. [2]2 P + 2 NaClO 2 + 2 H 2 O → Na 2 H 2 P 2 O 6 + 2 HCl. A mixture of hypophosphoric acid, phosphorous acid (H 3 PO 3) and phosphoric acid (H 3 PO 4) is produced when white phosphorus oxidises in air when partially immersed in water.
Neptunium(IV) phosphide can be formed from the fusion of stoichiometric amounts of neptunium and red phosphorus in an evacuated and sealed quartz tube at 750 °C: [2] [3] 3Np + 4P → Np 3 P 4 Physical properties