| rdfs:comment | - User can create, shape and manipulate Phosphorus, a highly reactive, poisonous, nonmetallic element occurring naturally in phosphates, especially apatite, and existing in three allotropic forms, white (or sometimes yellow), red, and black. Violet phosphorus is a form of phosphorus that can be produced by day-long annealing of red phosphorus above 550 °C. It does not ignite in air until heated to 300 °C, is insoluble in all solvents, is not attacked by alkali and reacts only slowly with halogens. It can be oxidised by nitric acid to phosphoric acid.
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| abstract | - User can create, shape and manipulate Phosphorus, a highly reactive, poisonous, nonmetallic element occurring naturally in phosphates, especially apatite, and existing in three allotropic forms, white (or sometimes yellow), red, and black. White phosphorus is a poisonous, colorless, semitransparent, soft, waxy solid that glows in the dark (phosphorescence) and is both highly flammable and self-igniting. It is the least stable, the most reactive, the most volatile, the least dense, and the most toxic of the allotropes. White phosphorus gradually changes to red phosphorus, which is accelerated by light and heat, and samples of white phosphorus almost always contain some red phosphorus and accordingly appear yellow. Red phosphorus is dull, reddish-brown cubic crystals or amorphous powder, that does not phosphoresce, and is not poisonous. 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, though it is still more stable than white phosphorus, which ignites at about 30 °C. After prolonged heating or storage, the color darkens; the resulting product is more stable and does not spontaneously ignite in air. Violet phosphorus is a form of phosphorus that can be produced by day-long annealing of red phosphorus above 550 °C. It does not ignite in air until heated to 300 °C, is insoluble in all solvents, is not attacked by alkali and reacts only slowly with halogens. It can be oxidised by nitric acid to phosphoric acid. Black phosphorus is the least reactive allotrope and the thermodynamically stable form below 550 °C, with appearance, properties and a structure very much like graphite, being black and flaky, a conductor of electricity, and having puckered sheets of linked atoms.
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