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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 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 Sodium hexametaphosphate (SHMP) is a salt of composition Na6 PO3)6 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 t ... References {{ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Hexametaphosphate
Sodium hexametaphosphate (SHMP) is a salt of composition Na6 PO3)6 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-staining an ... [...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. Although drawn with a particular resonance structure, the trianion has high symmetry. Synthesis and reactions Sodium dihydrogen phosphate is heated at 550 °C to give anhydrous trisodium trimetaphosphate: : The latter dissolves in water and precipitated by the addition of sodium chloride (common ion effect), affording the hexahydrate. STMP can also prepared by heating samples sodium polyphosphate. Hydrolysis of the ring leads to the acyclic sodium triphosphate: :Na3P3O9 + H2O → H2Na3P3O10 The analogous reaction of the metatriphosphate anion involves ring-opening by amine In chemistry, amines (, ) are compounds and functional groups that contain a basic n ... [...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. Although drawn with a particular resonance structure, the trianion has high symmetry. Synthesis and reactions Sodium dihydrogen phosphate is heated at 550 °C to give anhydrous trisodium trimetaphosphate: : The latter dissolves in water and precipitated by the addition of sodium chloride (common ion effect), affording the hexahydrate. STMP can also prepared by heating samples sodium polyphosphate. Hydrolysis of the ring leads to the acyclic sodium triphosphate: :Na3P3O9 + H2O → H2Na3P3O10 The analogous reaction of the metatriphosphate anion involves ring-opening by amine In chemistry, amines (, ) are compounds and functional groups that contain a basic n ... [...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, ca ... [...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 Aryl, aromatic substituents. They can be considered as esters of phosphoric acid. Like most functional groups, organophosphates occur in a diverse range of forms, with important examples including key biomolecules such as DNA, RNA and adenosine triphosphate, 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 popularity of OPEs as flame retardants came as a substitution for the highly regulated brominated flame retardants. 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 t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dihydrogen Phosphate
Dihydrogen phosphate or dihydrogenphosphate ion is an inorganic ion with the formula −. Phosphates occur widely in natural systems. These sodium phosphates are artificially used in food processing and packaging as emulsifying agents, neutralizing agents, surface-activating agents, and leavening agents providing humans with benefits. Emulsifying agents prevent separation of two ingredients in processed foods that would separate under natural conditions while neutralizing agents make processed foods taste fresher longer and lead to an increased shelf-life of these foods. Surface-activating agents prevent surface-tension formation on liquid-containing processed foods and finally, leavening agents are used in processed foods to aid in the expansion of yeast in baked goods. Dihydrogen phosphate is employed in the production of pharmaceuticals furthering their importance to medical practitioners of gastroenterology and humans in general. In this medical discipline, sodium phosphates ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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