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Phosphorus Oxide
Phosphorus oxide can refer to: * Phosphorus pentoxide (phosphorus(V) oxide, phosphoric anhydride), P2O5 * Phosphorus trioxide (phosphorus(III) oxide, phosphorous anhydride), P2O3 * Phosphorus tetroxide, * Several other, less common, oxides of phosphorus, including P4O7, P4O8, P4O9, and P2O6 Gases: * Phosphorus monoxide Phosphorus monoxide is an unstable radical inorganic compound with molecular formula P O. Phosphorus monoxide is notable as one of the few molecular compounds containing phosphorus that has been detected outside of Earth. Other phosphorus cont ..., PO * Phosphorus dioxide, {{Chemistry index ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorus Pentoxide
Phosphorus pentoxide is a chemical compound with molecular formula P4 O10 (with its common name derived from its empirical formula, P2O5). This white crystalline solid is the anhydride of phosphoric acid. It is a powerful desiccant and dehydrating agent. Structure Phosphorus pentoxide crystallizes in at least four forms or polymorphs. The most familiar one, a metastable form (shown in the figure), comprises molecules of P4O10. Weak van der Waals forces hold these molecules together in a hexagonal lattice (However, in spite of the high symmetry of the molecules, the crystal packing is not a close packing). The structure of the P4O10 cage is reminiscent of adamantane with ''T''d symmetry point group. It is closely related to the corresponding anhydride of phosphorous acid, P4O6. The latter lacks terminal oxo groups. Its density is 2.30 g/cm3. It boils at 423 °C under atmospheric pressure; if heated more rapidly it can sublimate. This form can be made by condensing the vap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorus Trioxide
Phosphorus trioxide is the chemical compound with the molecular formula P4O6. Although the molecular formula suggests the name tetraphosphorus hexaoxide, the name phosphorus trioxide preceded the knowledge of the compound's molecular structure, and its usage continues today. This colorless solid is structurally related to adamantane. It is formally the anhydride of phosphorous acid, H3PO3, but cannot be obtained by the dehydration of the acid. A white solid that melts at room temperature, it is waxy, crystalline and highly toxic, with garlic odour. Preparation It is obtained by the combustion of phosphorus in a limited supply of air at low temperatures. :P4 + 3 O2 → P4O6 By-products include red phosphorus suboxide. Chemical properties Phosphorus trioxide reacts with water to form phosphorous acid, reflecting the fact that it is the anhydride of that acid. : P4O6 + 6 H2O → 4 H3PO3 It reacts with hydrogen chloride to form H3PO3 and phosphorus trichloride. : P4O6 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorus Tetroxide
Diphosphorus tetroxide, or phosphorus tetroxide is an inorganic compound of phosphorus and oxygen. It has the empirical chemical formula . Solid phosphorus tetroxide (also referred to as phosphorus(III,V)-oxide) consists of variable mixtures of the mixed-valence oxides P4O7, P4O8 and P4O9. Preparation Phosphorus tetroxide can be produced by thermal decomposition of phosphorus trioxide, which disproportionates above 210 °C to form phosphorus tetroxide, with elemental phosphorus as a byproduct: :8P2O3 P4 + 6P2O4 In addition, phosphorus trioxide can be converted into phosphorus tetroxide by controlled oxidation with oxygen in carbon tetrachloride solution. Careful reduction of phosphorus pentoxide with red phosphorus Elemental phosphorus can exist in several allotropes, the most common of which are white and red solids. Solid violet and black allotropes are also known. Gaseous phosphorus exists as diphosphorus and atomic phosphorus. White phosphorus White ... at 4 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxide
An oxide () is a chemical compound that contains at least one oxygen atom and one other element in its chemical formula. "Oxide" itself is the dianion of oxygen, an O2– (molecular) ion. with oxygen in the oxidation state of −2. Most of the Earth's crust consists of oxides. Even materials considered pure elements often develop an oxide coating. For example, aluminium foil develops a thin skin of Al2O3 (called a passivation layer) that protects the foil from further corrosion.Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry of the Elements (2nd Edn.), Oxford:Butterworth-Heinemann. . Stoichiometry (the measurable relationship between reactants and chemical equations of a equation or reaction) Oxides are extraordinarily diverse in terms of stoichiometries and in terms of the structures of each stoichiometry. Most elements form oxides of more than one stoichiometry. A well known example is carbon monoxide and carbon dioxide.Greenwood, N. N.; & Earnshaw, A. (1997). Chemistry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorus
Phosphorus is a chemical element with the 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. It has a concentration in the Earth's crust of about one gram per kilogram (compare copper at about 0.06 grams). In minerals, phosphorus generally occurs as phosphate. Elemental phosphorus was first isolated as white phosphorus in 1669. White phosphorus emits a faint glow when exposed to oxygen – hence the name, taken from Greek mythology, meaning 'light-bearer' (Latin ), referring to the " Morning Star", the planet Venus. 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. The glow of phosphorus is caused by oxidation of the white (but not red) phosphorus — a process now called chem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorus Monoxide
Phosphorus monoxide is an unstable radical inorganic compound with molecular formula P O. Phosphorus monoxide is notable as one of the few molecular compounds containing phosphorus that has been detected outside of Earth. Other phosphorus containing molecules found in space include PN, PC, PC2, HCP and PH3. It was detected in the circumstellar shell of VY Canis Majoris and in the star forming region catalogued as AFGL 5142. The compound has been found to have been initially produced in star-forming regions, and speculated to be carried by interstellar comets throughout outer space, including to the early Earth. Phosphorus monoxide plays a role in the phosphorescence of phosphorus. Discovery In 1894 W. N. Hartley was the first to report an observation of ultraviolet emission from a phosphorus compound, that was later expanded on by Geuter. The source of the spectral lines and bands were known to be related to phosphorus, but the exact nature was unknown. In 1927 H. J. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
