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Borate
A borate is any of several boron oxyanions, negative ions consisting of boron and oxygen, such as orthoborate , metaborate , or tetraborate ; or any salt with such anions, such as sodium metaborate, and disodium tetraborate . The name also refers to certain functional groups in molecules consisting of boron and oxygen, and esters with such groups, such as triethyl orthoborate . Natural occurrence Borate ions occur, alone or with other anions, in many borate and borosilicate minerals such as borax, boracite, ulexite (boronatrocalcite) and colemanite. Borates also occur in seawater, where they make an important contribution to the absorption of low frequency sound in seawater. Borates also occur in plants, including almost all fruits. Anions The main borate anions are: * tetrahydroxyborate , found in sodium tetrahydroxyborate . * orthoborate , found in trisodium orthoborate * perborate , as in sodium perborate * metaborate or , found in sodium metaborate * diborate , f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Borate Mineral
The borate minerals are minerals which contain a borate anion group. The borate (BO3) units may be polymerised similar to the SiO4 unit of the silicate mineral class. This results in B2O5, B3O6, B2O4 anions as well as more complex structures which include hydroxide or halogen anions.Klein, Cornelis and Cornelius Hurlbut, Jr., ''Manual of Mineralogy'', Wiley, 20th ed., 1985 pp. 343 - 347 The (O,OH)4sup>− anion exists as well. Many borate minerals, such as borax, colemanite, and ulexite, are salts: soft, readily soluble, and found in evaporite contexts. However, some, such as boracite, are hard and resistant to weathering, more similar to the silicates. There are over 100 different borate minerals. Vanadates), 09 Silicates: * ''neso-'': insular (from Greek , "island") * ''soro-'': grouped (from Greek , "heap, pile, mound") * ''cyclo-'': rings of (from Greek , "circle") * ''ino-'': chained (from Greek , "fibre", rom Ancient Greek * ''phyllo-'': sheets of (from Greek , ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metaborate
A metaborate is an anion (negative ion) consisting of boron and oxygen, with empirical formula ; or any salt with such anions, such as sodium metaborate, or calcium metaborate . It is one of the boron oxoanions or borates In aqueous solutions this anion hydrolyzes to tetrahydroxyborate . For this reason, solutions or hydrated salts of the latter are often improperly named "metaborate". Structure Solid state In the solid state salts, metaborate is often an oligomeric or polymeric anion, conceptually resulting from the fusion of two or more through shared oxygen atoms. In these anions, the boron atom forms covalent bonds with either three or four oxygen atoms. Some of the structures are * A trimer with formula or , consisting of a six-member ring of alternating boron an oxygen atoms with three extra oxygen atom attached to the borons. This form is found, for example, in some anhydrous alkali metal salts like sodium metaborate or potassium metaborate, in α- and β- barium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Metaborate
Sodium metaborate is a chemical compound of sodium, boron, and oxygen with formula . However, the metaborate ion is trimeric in the anhydrous solid, therefore a more correct formula is or . The formula can be written also as · to highlight the relation to the main oxides of sodium and boron. The name is also applied to several hydrates whose formulas can be written for various values of ''n''. The anhydrous and hydrates are colorless crystalline solids. The anhydrous form is hygroscopic. Hydrates and solubility The following hydrates crystallize from solutions of the proper composition in various temperature ranges: * tetrahydrate ·4 from −6 to 53.6 °C * dihydrate ·2 from 53.6 °C to 105 °C * hemihydrate ·0.5 from 105 °C to the boiling point. Early reports of a monohydrate · have not been confirmed. Structure Anhydrous Solid anhydrous sodium metaborate has the hexagonal crystal system with space group R\bar3 c. It actually contains the trimeric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boron
Boron is a chemical element with the symbol B and atomic number 5. In its crystalline form it is a brittle, dark, lustrous metalloid; in its amorphous form it is a brown powder. As the lightest element of the ''boron group'' it has three valence electrons for forming covalent bonds, resulting in many compounds such as boric acid, the mineral borax, sodium borate, and the ultra-hard crystals of boron carbide and boron nitride. Boron is synthesized entirely by cosmic ray spallation and supernovae and not by stellar nucleosynthesis, so it is a low-abundance element in the Solar System and in the Crust (geology), Earth's crust. It constitutes about 0.001 percent by weight of Earth's crust. It is concentrated on Earth by the water-solubility of its more common naturally occurring compounds, the borate minerals. These are mined industrially as evaporites, such as borax and kernite. The largest known deposits are in Turkey, the largest producer of boron minerals. Elemental b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrahydroxyborate
Tetrahydroxyborate is an inorganic anion with the chemical formula or . It contributes no colour to tetrahydroxyborate salts. It is found in the mineral hexahydroborite, , originally formulated . It is one of the boron oxoanions, and acts as a weak base. The systematic names are tetrahydroxyboranuide (substitutive) and tetrahydroxidoborate(1−) (additive). It can be viewed as the conjugate base of boric acid. Structure Tetrahydroxyborate has a symmetric tetrahedral geometry, isoelectronic with the hypothetical compound orthocarbonic acid . Chemical properties Basicity Tetrahydroxyborate act as a weak Brønsted–Lowry base because it can assimilate a proton (), yielding boric acid with release of water: : + + It can also release a hydroxy anion , thus acting as a classical Arrhenius base: : + (pK = 9.14 to the left) Thus, when boric acid is dissolved in pure (neutral) water, most of it will exist as tetrahydroxyborate ions. With diols In aqueous solution, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Perborate
Sodium perborate is chemical compound whose chemical formula may be written , , or, more properly, ·. Its name is sometimes abbreviated as PBS (not to be confused with phosphate-buffered saline). The compound is commonly encountered in anhydrous form or as a hexahydrate (commonly called "monohydrate" or PBS-1 and "tetrahydrate" or PBS-4, after the early assumption that would be the anhydrous form).Alexander McKillop and William R Sanderson (1995): "Sodium perborate and sodium percarbonate: Cheap, safe and versatile oxidising agents for organic synthesis". ''Tetrahedron'', volume 51, issue 22, pages 6145-6166. They are both white, odorless, water-soluble solids.B.J. Brotherton "Boron: Inorganic Chemistry" in ''Encyclopedia of Inorganic Chemistry'' (1994) Ed. R. Bruce King, John Wiley & Sons This salt is widely used in laundry detergents, as one of the peroxide-based bleaches. Structure Unlike sodium percarbonate and sodium perphosphate, the compound is not simply an adduct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trisodium Orthoborate
Trisodium borate is a chemical compound of sodium, boron, and oxygen, with formula , or . It is a salt with the orthoborate anion . The compound is also called trisodium orthoborate, sodium orthoborate, or just sodium borate. However, "sodium orthoborate" has been used also for a compound with formula , which would correspond to an equimolar mixture of sodium metaborate and trisodium borate proper. and "sodium borate" is sometimes used in the generic sense, for a sodium salt with any of several other borate anions. Preparation Sodium carbonate will react with sodium metaborate or boric oxide to form the orthoborate and carbon dioxide when heated between 600 and 850 °C: : + → + Difficult to obtain in pure form from melts. Properties Reactions When dissolved in water, the orthoborate anion partially hydrolyzes into metaborate and hydroxide : : + + 3 Electrolysis of a solution of sodium orthoborate generates sodium perborate at the anode An a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Borax
Borax is a salt (ionic compound), a hydrated borate of sodium, with chemical formula often written . It is a colorless crystalline solid, that dissolves in water to make a basic solution. It is commonly available in powder or granular form, and has many industrial and household uses, including as a pesticide, as a metal soldering flux, as a component of glass, enamel, and pottery glazes, for tanning of skins and hides, for artificial aging of wood, as a preservative against wood fungus, and as a pharmaceutic alkalizer. In chemical laboratories, it is used as a buffering agent. The compound is often called sodium tetraborate decahydrate, but that name is not consistent with its structure. The anion is not tetraborate but tetrahydroxy tetraborate , so the more correct formula should be . Informally, the product is often called sodium borate decahydrate or just sodium borate. The terms tincal "tinkle" and tincar "tinker" refer to native borax, historically mined from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disodium Tetraborate
Borax is a salt (ionic compound), a hydrated borate of sodium, with chemical formula often written . It is a colorless crystalline solid, that dissolves in water to make a basic solution. It is commonly available in powder or granular form, and has many industrial and household uses, including as a pesticide, as a metal soldering flux, as a component of glass, enamel, and pottery glazes, for tanning of skins and hides, for artificial aging of wood, as a preservative against wood fungus, and as a pharmaceutic alkalizer. In chemical laboratories, it is used as a buffering agent. The compound is often called sodium tetraborate decahydrate, but that name is not consistent with its structure. The anion is not tetraborate but tetrahydroxy tetraborate , so the more correct formula should be . Informally, the product is often called sodium borate decahydrate or just sodium borate. The terms tincal "tinkle" and tincar "tinker" refer to native borax, historically mined from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthoborate
In inorganic chemistry, an orthoborate is a polyatomic anion with formula or a salt containing the anion; such as trisodium orthoborate . It is one of several boron oxoanions, or borates. The name is also used in organic chemistry for the trivalent functional group , or any compound (ester) that contains it, such as triethyl orthoborate . Structure The orthoborate ion is known in the solid state, for example, in calcium orthoborate , where it adopts a nearly trigonal planar structure. It is a structural analogue of the carbonate anion , with which it is isoelectronic. Simple bonding theories point to the trigonal planar structure. In terms of valence bond theory, the bonds are formed by using sp2 hybrid orbitals on boron. Some compounds termed orthoborates do not necessarily contain the trigonal planar ion. For example, gadolinium orthoborate contains the planar ion only a high temperatures; otherwise it contains the polyborate anion . Reactions Solution When orthobora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ulexite
Ulexite (NaCaB5O6(OH)6·5H2O, hydrated sodium calcium borate hydroxide), sometimes known as TV rock or Television stone, is a mineral occurring in silky white rounded crystalline masses or in parallel fibers. The natural fibers of ulexite conduct light along their long axes, by internal reflection. Ulexite was named for the German chemist Georg Ludwig Ulex (1811–1883) who first discovered it. Ulexite is a structurally complex mineral, with a basic structure containing chains of sodium, water and hydroxide octahedra. The chains are linked together by calcium, water, hydroxide and oxygen polyhedra and massive boron units. The boron units have a formula of 5O6(OH)6sup>3– and a charge of −3. They are composed of three borate tetrahedra and two borate triangular groups. Ulexite is found in evaporite deposits and the precipitated ulexite commonly forms a "cotton ball" tuft of acicular crystals. Ulexite is frequently found associated with colemanite, borax, meyerhofferite, hydro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sodium Tetrahydroxyborate
Sodium tetrahydroxyborate is a salt (ionic compound) of with chemical formula or . It is one of several sodium borates. At room temperature it is a colorless transparent crystalline solid. The element ratio corresponds to the oxide mixture , but the structure of the solid is quite different from that suggested by this formula. Structure Sodium tetrahydroxyborate has been crystallized from aqueous solutions in two anhydrous forms. Both contain the tetrahedral tetrahydroxyborate anion, which is formed from (ortho)boric acid in water solutions by binding an hydroxide anion instead of loss of a proton . These anions lie in layers perpendicular to the (010) plane, and form a tridimensional lattice held together by hydrogen bonds between the hydrogen atoms in each anion and the oxygen atoms in adjacent anions. Monoclinic form The first form, described in 1993, crystallizes in the monoclinic crystal system with symmetry group ''P''21/''a'' and parameters ''a'' = 588.6 pm, ''b'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
