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Metaphosphate
A metaphosphate ion is an oxyanion that has the empirical formula . It was first postulated in 1955 but was not observed until 1979, when it was detected by mass spectrometry. Metaphosphate is an intermediate in the hydrolysis of phosphate esters but it is difficult to isolate, as it readily hydrolyses to from a dihydrogen phosphate Dihydrogen phosphate is an inorganic ion with the formula 2PO4sup>−. Phosphates occur widely in natural systems. Perhaps the most common salt of dihydrogen phosphate is sodium dihydrogen phosphate. It is used in animal feed, fertilizer, ... ion () and tends to self-react in the absence of water to form rings or infinite chains: These species are also called metaphosphates and are generally stable, with some such as sodium trimetaphosphate being produced on an industrial scale. Metaphosphates can be used as an alternative of white phosphorus in organic syntheses. See also * Sodium trimetaphosphate * Sodium hexametaphosphate References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Hexametaphosphate
Sodium hexametaphosphate (SHMP) is a salt (chemistry), salt of composition . Sodium hexametaphosphate of commerce is typically a mixture of metaphosphates (empirical formula: NaPO3), of which the hexamer is one, and is usually the compound referred to by this name. Such a mixture is more correctly termed sodium polymetaphosphate. They are white solids that dissolve in water. Uses SHMP is used as a sequestrant and has applications within a wide variety of industries, including as a food additive in which it is used under the E number E452i. Sodium carbonate is sometimes added to SHMP to raise the pH to 8.0–8.6, which produces a number of SHMP products used for water softening and detergents. A significant use for sodium hexametaphosphate is as a deflocculant in the production of clay-based ceramic particles. It is also used as a dispersing agent to break down clay and other soil types for soil texture assessment. It is used as an active ingredient in toothpastes as an anti-stai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Trimetaphosphate
Sodium trimetaphosphate (also STMP), with formula Na3P3O9, is one of the metaphosphates of sodium. It has the formula but the hexahydrate is also well known. It is the sodium salt of trimetaphosphoric acid. It is a colourless solid that finds specialised applications in food and construction industries: it is used as a phosphorylating agent for ascorbic acid to stabilize vitamin C mixtures against thermal decomposition; in the construction industry, sodium trimetaphosphate is used to prevent the shrinkage of gypsum plaster boards (US Pat. 03/0154888) and as a setting retarder for gypsum plaster. Although drawn with a particular resonance structure, the trianion has high symmetry. Synthesis and reactions Trisodium trimetaphosphate is produced industrially by heating sodium dihydrogen phosphate to 550 °C, a method first developed in 1955: : The trimetaphosphate dissolves in water and is precipitated by the addition of sodium chloride ( common ion effect), affording the hex ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxyanion
An oxyanion, or oxoanion, is an ion with the generic formula (where A represents a chemical element and O represents an oxygen atom). Oxyanions are formed by a large majority of the chemical elements. The formulae of simple oxyanions are determined by the octet rule. The corresponding oxyacid of an oxyanion is the compound . The structures of condensed oxyanions can be rationalized in terms of AO''n'' polyhedral units with sharing of corners or edges between polyhedra. The oxyanions (specifically, phosphate and polyphosphate esters) adenosine monophosphate ( AMP), adenosine diphosphate ( ADP) and adenosine triphosphate (ATP) are important in biology. Monomeric oxyanions The formula of monomeric oxyanions, , is dictated by the oxidation state of the element A and its position in the periodic table. Elements of the first row are limited to a maximum coordination number of 4. However, none of the first row elements has a monomeric oxyanion with that coordination number. Instead, c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphate Ester
In organic chemistry, organophosphates (also known as phosphate esters, or OPEs) are a class of organophosphorus compounds with the general structure , a central phosphate molecule with alkyl or aromatic substituents. They can be considered as esters of phosphoric acid. Organophosphates are best known for their use as pesticides. Like most functional groups, organophosphates occur in a diverse range of forms, with important examples including key biomolecules such as DNA, RNA and ATP, as well as many insecticides, herbicides, nerve agents and flame retardants. OPEs have been widely used in various products as flame retardants, plasticizers, and performance additives to engine oil. The low cost of production and compatibility to diverse polymers made OPEs to be widely used in industry including textile, furniture, electronics as plasticizers and flame retardants. These compounds are added to the final product physically rather than by chemical bond. Due to this, OPEs leak into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dihydrogen Phosphate
Dihydrogen phosphate is an inorganic ion with the formula 2PO4sup>−. Phosphates occur widely in natural systems. Perhaps the most common salt of dihydrogen phosphate is sodium dihydrogen phosphate. It is used in animal feed, fertilizer, buffer (in food), and treating metal surfaces. Structure The dihydrogen phosphate anion consists of a central phosphorus atom Atoms are the basic particles of the chemical elements. An atom consists of a atomic nucleus, nucleus of protons and generally neutrons, surrounded by an electromagnetically bound swarm of electrons. The chemical elements are distinguished fr ... bonded two oxides and two hydroxy groups in a tetrahedral arrangement. Acid-base equilibria Dihydrogen phosphate can be both a hydrogen donor and acceptor. Examples * Ammonium dihydrogen phosphate ((NH4)(H2PO4)) * Monocalcium phosphate (Ca(H2PO4)2) Safety Many foods including milk, eggs, poultry, and nuts contain these sodium phosphates. Notes References ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
