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Monofluorophosphate
Monofluorophosphate is an anion with the formula PO3F2−, which is a phosphate group with one oxygen atom substituted with a fluoride atom. The charge of the ion is −2. The ion resembles sulfate in size, shape and charge, and can thus form compounds with the same structure as sulfates. These include Tutton's salts and langbeinites. The most well-known compound of monofluorophosphate is sodium monofluorophosphate, commonly used in toothpaste. Related ions include difluorophosphate () and hexafluorophosphate (). The related neutral molecule is phosphenic fluoride PO2F. Organic derivatives can be highly toxic and include diisopropyl fluorophosphate. Some of the Novichok agents are monofluorophosphate esters. Names are given to these by naming the groups attached as esters and then adding "fluorophosphonate" to the end of the name. Two organic groups can be attached. Other related nerve gas substances may not be esters, and instead have carbon-phosphorus or nitrogen-phosphorus b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Monofluorophosphate
Sodium monofluorophosphate, commonly abbreviated SMFP, is an inorganic compound with the chemical formula Na2PO3F. Typical for a salt, MFP is odourless, colourless, and water-soluble. This salt is an ingredient in some toothpastes.Klaus Schrödter, Gerhard Bettermann, Thomas Staffel, Friedrich Wahl, Thomas Klein, Thomas Hofmann "Phosphoric Acid and Phosphates" in ''Ullmann’s Encyclopedia of Industrial Chemistry'' 2008, Wiley-VCH, Weinheim. Uses MFP is best known as an ingredient in some toothpastes.Wolfgang Weinert "Oral Hygiene Products" in ''Ullmann’s Encyclopedia of Industrial Chemistry'' 2000, Wiley-VCH, Weinheim. It functions as a source of fluoride via the following hydrolysis reaction: :PO3F2− + OH− → HPO42− + F− Fluoride protects tooth enamel from attack by bacteria that cause dental caries (cavities). Although developed by a chemist at Procter and Gamble, its use in toothpaste (Colgate toothpaste and Ultra Brite) was patented by Colgate-Palmolive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tutton's Salts
Tutton's salts are a family of salts with the formula M2M'(SO4)2(H2O)6 (sulfates) or M2M'(SeO4)2(H2O)6 (selenates). These materials are double salts, which means that they contain two different cations, M+ and M'2+ crystallized in the same regular ionic lattice. The univalent cation can be potassium, rubidium, cesium, ammonium (NH4), deuterated ammonium (ND4) or thallium. Sodium or lithium ions are too small. The divalent cation can be magnesium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc or cadmium. In addition to sulfate and selenate, the divalent anion can be chromate (CrO42−), tetrafluoroberyllate (BeF42−), hydrogenphosphate (HPO42−) or monofluorophosphate (PO3F2−). Tutton's salts crystallize in the monoclinic space group ''P''21/''a''. The robustness is the result of the complementary hydrogen-bonding between the tetrahedral anions and cations as well their interactions with the metal aquo complex (H2O)6sup>2+. Examples and related compoun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead(II) Oxide
Lead(II) oxide, also called lead monoxide, is the inorganic compound with the molecular formula Pb O. PbO occurs in two polymorphs: litharge having a tetragonal crystal structure, and massicot having an orthorhombic crystal structure. Modern applications for PbO are mostly in lead-based industrial glass and industrial ceramics, including computer components. It is an amphoteric oxide. Types Lead oxide exists in two types: * Red tetragonal (α-PbO), obtained at lower temperatures than the β-PbO * Yellow orthorhombic (β-PbO), which is obtained temperatures higher than Synthesis PbO may be prepared by heating lead metal in air at approximately . At this temperature it is also the end product of decomposition of other oxides of lead in air: :PbO2->[] Pb12O19 ->[] Pb12O17 ->[] Pb3O4 ->[] PbO Thermal decomposition of lead(II) nitrate or lead carbonate, lead(II) carbonate also results in the formation of PbO: :2 → 2 PbO + 4 + : → PbO + PbO is produced ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Birefringence
Birefringence is the optical property of a material having a refractive index that depends on the polarization and propagation direction of light. These optically anisotropic materials are said to be birefringent (or birefractive). The birefringence is often quantified as the maximum difference between refractive indices exhibited by the material. Crystals with non-cubic crystal structures are often birefringent, as are plastics under mechanical stress. Birefringence is responsible for the phenomenon of double refraction whereby a ray of light, when incident upon a birefringent material, is split by polarization into two rays taking slightly different paths. This effect was first described by Danish scientist Rasmus Bartholin in 1669, who observed it in calcite, a crystal having one of the strongest birefringences. In the 19th century Augustin-Jean Fresnel described the phenomenon in terms of polarization, understanding light as a wave with field components in transverse polariz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver Pyrophosphate
Silver phosphate or silver orthophosphate is a light sensitive, yellow, water-insoluble chemical compound composed of silver and phosphate ions of formula Ag3PO4. Synthesis, reactions and properties Silver phosphate is formed as a yellow solid precipitate by the reaction between a soluble silver salt, such as silver nitrate, with a soluble orthophosphate. Its solubility product is 8.89×10−17 mol4·dm−2. The precipitation reaction is analytically significant and can be used in qualitative or quantitative and quantitative analysis. This compound dissolves in aqueous ammonia. Large crystals of silver phosphate form upon gradual evaporation of such ammoniacal solutions. Its structure has been confirmed by X-ray crystallography. Uses The precipitation of silver phosphate is useful in traditional analytical chemistry. Precipitation of silver phosphate is also used in silver staining of biological materials (after reduction to silver metal) - as a magnifying agent for phosphat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver Phosphate
Silver phosphate or silver orthophosphate is a light sensitive, yellow, water-insoluble chemical compound composed of silver and phosphate ions of formula Ag3PO4. Synthesis, reactions and properties Silver phosphate is formed as a yellow solid precipitate by the reaction between a soluble silver salt, such as silver nitrate, with a soluble orthophosphate. Its solubility product is 8.89×10−17 mol4·dm−2. The precipitation reaction is analytically significant and can be used in qualitative or quantitative and quantitative analysis. This compound dissolves in aqueous ammonia. Large crystals of silver phosphate form upon gradual evaporation of such ammoniacal solutions. Its structure has been confirmed by X-ray crystallography. Uses The precipitation of silver phosphate is useful in traditional analytical chemistry. Precipitation of silver phosphate is also used in silver staining of biological materials (after reduction to silver metal) - as a magnifying agent for phosphat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphoryl Fluoride
Phosphoryl fluoride (commonly called phosphorus oxyfluoride) is a compound with the chemical formula . It is a colorless gas that hydrolyzes rapidly. Synthesis and reactions Phosphorus oxyfluoride is prepared by partial hydrolysis of phosphorus pentafluoride. Phosphorus oxyfluoride is the progenitor of the simple fluorophosphoric acids by hydrolysis. The sequence starts with difluorophosphoric acid: : The next steps give monofluorophosphoric acid and phosphoric acid: : : Phosphoryl fluoride combines with dimethylamine to produce dimethylaminophosphoryl difluoride and difluorophosphate and hexafluorophosphate Hexafluorophosphate is an anion with chemical formula of . It is an octahedral species that imparts no color to its salts. is isoelectronic with sulfur hexafluoride, , and the hexafluorosilicate dianion, , and hexafluoroantimonate . In this anio ... ions. References {{inorganic-compound-stub Oxyfluorides Phosphorus oxohalides Phosphorus(V) compounds ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver Monofluorophosphate
Silver is a chemical element with the symbol Ag (from the Latin ', derived from the Proto-Indo-European ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. The metal is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc refining. Silver has long been valued as a precious metal. Silver metal is used in many bullion coins, sometimes alongside gold: while it is more abundant than gold, it is much less abundant as a native metal. Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of the seven metals of antiquity, silver has had an enduring role in most human cultures. Other than i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urea
Urea, also known as carbamide, is an organic compound with chemical formula . This amide has two amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest amide of carbamic acid. Urea serves an important role in the metabolism of nitrogen-containing compounds by animals and is the main nitrogen-containing substance in the urine of mammals. It is a colorless, odorless solid, highly soluble in water, and practically non-toxic ( is 15 g/kg for rats). Dissolved in water, it is neither acidic nor alkaline. The body uses it in many processes, most notably nitrogen excretion. The liver forms it by combining two ammonia molecules () with a carbon dioxide () molecule in the urea cycle. Urea is widely used in fertilizers as a source of nitrogen (N) and is an important raw material for the chemical industry. In 1828 Friedrich Wöhler discovered that urea can be produced from inorganic starting materials, which was an important conceptual milestone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrasodium Pyrophosphate
Tetrasodium pyrophosphate, also called sodium pyrophosphate, tetrasodium phosphate or TSPP, is an inorganic compound with the chemical formula, formula Na4P2O7. As a salt, it is a white, water-soluble solid. It is composed of pyrophosphate anion and sodium ions. Toxicity is approximately twice that of table salt when ingested orally.Handbook of food toxicology', S. S. Deshpande, page 260 Also known is the decahydrate Na4P2O710(H2O). D.L. Perry S.L. Phillips (1995) ''Handbook of inorganic compounds'' CRC Press Use Tetrasodium pyrophosphate is used as a buffering agent, an emulsifier, a dispersing agent, and a thickening agent, and is often used as a food additive. Common foods containing tetrasodium pyrophosphate include chicken nuggets, marshmallows, pudding, crab meat, imitation crab, canned tuna, and soy-based meat alternatives and cat foods and cat treats where it is used as a palatability enhancer. In toothpaste and dental floss, tetrasodium pyrophosphate acts as a Calculus ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disodium Hydrogen Phosphate
Disodium phosphate (DSP), or disodium hydrogen phosphate, or sodium phosphate dibasic, is the inorganic compound with the formula Na2HPO4. It is one of several sodium phosphates. The salt is known in anhydrous form as well as forms with 2, 7, 8, and 12 hydrates. All are water-soluble white powders; the anhydrous salt being hygroscopic. The pH of disodium hydrogen phosphate water solution is between 8.0 and 11.0, meaning it is moderately basic: :HPO42− + H2O H2PO4− + OH− Production and reactions It can be generated by neutralization of phosphoric acid with sodium hydroxide: :H3PO4 + 2 NaOH → Na2HPO4 + 2 H2O Industrially It is prepared in a two-step process by treating dicalcium phosphate with sodium bisulfate, which precipitates calcium sulfate:Klaus Schrödter, Gerhard Bettermann, Thomas Staffel, Friedrich Wahl, Thomas Klein, Thomas Hofmann "Phosphoric Acid and Phosphates" in ''Ullmann’s Encyclopedia of Industrial Chemistry'' 2008, Wiley-VCH, Weinhei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
