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Tungsten Hexabromide
Tungsten hexabromide, also known as tungsten(VI) bromide, is a chemical compound of tungsten and bromine with the formula . It is an air-sensitive dark grey powder that decomposes above 200 °C to tungsten(V) bromide and bromine. Production and reactions Tungsten hexabromide is mainly produced by the reaction of metallic tungsten and bromine at temperatures around 100 °C in a nitrogen atmosphere: : Another method of producing this compound is by the reaction of tungsten hexacarbonyl and bromine at room temperature, releasing carbon monoxide. It can also be produced by the metathesis reaction of boron tribromide and tungsten hexachloride. is reduced with elemental antimony at elevated temperatures, consecutively producing, , , , , then finally at 350 °C. This reaction produces antimony tribromide as a side product. Any of these bromides can be reverted to the hexabromide by oxidation with bromine at 160 °C. Tungsten hexabromide is hydrolyzed in water, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethanol
Ethanol (also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound with the chemical formula . It is an Alcohol (chemistry), alcohol, with its formula also written as , or EtOH, where Et is the pseudoelement symbol for ethyl group, ethyl. Ethanol is a Volatility (chemistry), volatile, flammable, colorless liquid with a characteristic wine-like odor and pungent taste. As a psychoactive depressant, it is the active ingredient in alcoholic beverages, and the second most consumed drug globally behind caffeine. Ethanol is naturally produced by the fermentation process of sugars by yeasts or via petrochemical processes such as ethylene hydration. Historically it was used as a general anesthetic, and has modern medical applications as an antiseptic, disinfectant, solvent for some medications, and antidote for methanol poisoning and ethylene glycol poisoning. It is used as a chemical solvent and in the Chemical synthesis, synthesis of orga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Monoxide
Carbon monoxide (chemical formula CO) is a poisonous, flammable gas that is colorless, odorless, tasteless, and slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simplest oxocarbon, carbon oxide. In coordination complexes, the carbon monoxide ligand is called ''metal carbonyl, carbonyl''. It is a key ingredient in many processes in industrial chemistry. The most common source of carbon monoxide is the partial combustion of carbon-containing compounds. Numerous environmental and biological sources generate carbon monoxide. In industry, carbon monoxide is important in the production of many compounds, including drugs, fragrances, and fuels. Indoors CO is one of the most acutely toxic contaminants affecting indoor air quality. CO may be emitted from tobacco smoke and generated from malfunctioning fuel-burning stoves (wood, kerosene, natural gas, propane) and fuel-burning heating systems (wood, oil, n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tungsten(VI) Oxide
Tungsten(VI) oxide, also known as tungsten trioxide is a chemical compound of oxygen and the transition metal tungsten, with formula WO3. The compound is also called tungstic anhydride, reflecting its relation to tungstic acid . It is a light yellow crystalline solid. Tungsten(VI) oxide occurs naturally in the form of hydrates, which include minerals: tungstite WO3·H2O, meymacite WO3·2H2O and hydrotungstite (of the same composition as meymacite, however sometimes written as H2WO4). These minerals are rare to very rare secondary tungsten minerals. History In 1841, a chemist named Robert Oxland gave the first procedures for preparing tungsten trioxide and sodium tungstate. He was granted patents for his work soon after, and is considered to be the founder of systematic tungsten chemistry. Structure and properties The crystal structure of tungsten trioxide is temperature dependent. It is tetragonal at temperatures above 740 °C, orthorhombic from 330 to 740 °C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tungsten(VI) Oxytetrabromide
Tungsten(VI) oxytetrabromide is the inorganic compound with the formula . This a red-brown, hygroscopic solid sublimes at elevated temperatures. It forms adducts with Lewis bases. The solid consists of weakly associated square pyramidal monomers. The related tungsten(VI) oxytetrachloride has been more heavily studied. The compound is usually classified as an oxyhalide. It can be produced by the reaction of tungsten hexabromide and tungsten trioxide Tungsten(VI) oxide, also known as tungsten trioxide is a chemical compound of oxygen and the transition metal tungsten, with formula WO3. The compound is also called tungstic anhydride, reflecting its relation to tungstic acid . It is a light ...: : References Tungsten(VI) compounds Oxobromides {{inorganic-compound-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tungsten Pentoxide
Tungsten pentoxide () was reported in early literature but proved to have the stoichiometry W18O49.Wells A.F. (1984) ''Structural Inorganic Chemistry'' 5th edition Oxford Science Publications Sometimes called mineral blue, it is a blue solid formed by the reaction of tungsten trioxide, WO3, and tungsten metal at 700 °C. Intermediate oxides of tungsten There are a number of these unusual intermediate oxides formed from reacting metal and trioxide, including W20O58 and W24O70. W18O49 contains both octahedral and pentagonal bipyramidal co-ordination of the metal atoms by oxygen. See also *Tungsten(III) oxide *Tungsten(IV) oxide *Tungsten(VI) oxide Tungsten(VI) oxide, also known as tungsten trioxide is a chemical compound of oxygen and the transition metal tungsten, with formula WO3. The compound is also called tungstic anhydride, reflecting its relation to tungstic acid . It is a light ... References Tungsten(V) compounds Transition metal oxides {{inorganic-com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antimony Tribromide
Antimony tribromide ( Sb Br3) is a chemical compound containing antimony in its +3 oxidation state. Production Antimony tribromide may be made by the reaction of antimony with elemental bromine, or by the reaction of antimony trioxide with hydrobromic acid. Alternatively, it can be prepared by the action of bromine on a mixture of antimony sulfide and antimony trioxide at 250 °C. Chemical properties Antimony tribromide has two crystalline forms, both having orthorhombic symmetries. When a warm carbon disulfide solution of SbBr3 is rapidly cooled, it crystallizes into the needle-like α-SbBr3, which then slowly converts to the more stable β form. Antimony tribromide hydrolyzes in water to form hydrobromic acid and antimony trioxide: : 2 SbBr3 + 3 H2O → Sb2O3 + 6 HBr Uses It can be added to polymers such as polyethylene as a fire retardant. It is also used in the production of other antimony compounds, in chemical analysis, as a mordant A mordant or dye fixative is a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tungsten(II) Bromide
Tungsten (also called wolfram) is a chemical element; it has symbol W and atomic number 74. It is a metal found naturally on Earth almost exclusively in compounds with other elements. It was identified as a distinct element in 1781 and first isolated as a metal in 1783. Its important ores include scheelite and wolframite, the latter lending the element its alternative name. The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all known elements, melting at . It also has the highest boiling point, at . Its density is 19.254 g/cm3, comparable with that of uranium and gold, and much higher (about 1.7 times) than that of lead. Polycrystalline tungsten is an intrinsically brittle and hard material (under standard conditions, when uncombined), making it difficult to work into metal. However, pure single-crystalline tungsten is more ductile and can be cut with a hard-steel hacksaw. Tungsten occurs in many alloys, whic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antimony
Antimony is a chemical element; it has chemical symbol, symbol Sb () and atomic number 51. A lustrous grey metal or metalloid, it is found in nature mainly as the sulfide mineral stibnite (). Antimony compounds have been known since ancient times and were powdered for use as medicine and cosmetics, often known by the Arabic name Kohl (cosmetics), kohl. The earliest known description of this metalloid in the West was written in 1540 by Vannoccio Biringuccio. China is the largest producer of antimony and its compounds, with most production coming from the Xikuangshan Mine in Hunan. The industrial methods for refining antimony from stibnite are Roasting (metallurgy), roasting followed by carbothermic reaction, reduction with carbon, or direct reduction of stibnite with iron. The most common applications for metallic antimony are in alloys with lead and tin, which have improved properties for solders, Bullet, bullets, and plain bearings. It improves the rigidity of lead-alloy pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tungsten Hexachloride
Tungsten hexachloride is an inorganic chemical compound of tungsten and chlorine with the chemical formula . This dark violet-blue compound exists as volatile crystals under standard conditions. It is an important starting reagent in the preparation of tungsten compounds. Other examples of charge-neutral hexachlorides are rhenium(VI) chloride and molybdenum(VI) chloride. The highly volatile tungsten hexafluoride is also known. As a d0 atom, tungsten hexachloride is diamagnetic. Preparation and structure Tungsten hexachloride can be prepared by chlorinating tungsten metal in a sealed tube at 600 °C: : Tungsten hexachloride exists in both blue and red polymorphs, referred to respectively as α and β. The wine-red β can be obtained by rapid cooling, whereas the blue α form is more stable at room temperature. Although these polymorphs are distinctly colored, their molecular structures are very similar. Both polymorphs feature molecules that have octahedral geometry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boron Tribromide
Boron tribromide, BBr3, is a colorless, fuming liquid compound containing boron and bromine. Commercial samples usually are amber to red/brown, due to weak bromine contamination. It is decomposed by water and alcohols. Chemical properties Boron tribromide is commercially available and is a strong Lewis acid. It is an excellent demethylating or dealkylating agent for the cleavage of ethers, also with subsequent cyclization, often in the production of pharmaceuticals. The mechanism of dealkylation of tertiary alkyl ethers proceeds via the formation of a complex between the boron center and the ether oxygen followed by the elimination of an alkyl bromide to yield a dibromo(organo)borane. :ROR + BBr3 → RO+(−BBr3)R → ROBBr2 + RBr Aryl methyl ethers (as well as activated primary alkyl ethers), on the other hand are dealkylated through a bimolecular mechanism involving two BBr3-ether adducts. :RO+(−BBr3)CH3 + RO+(−BBr3)CH3 → RO(−BBr3) + CH3Br + R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tungsten Hexacarbonyl
Tungsten hexacarbonyl (also called tungsten carbonyl) is an organometallic compound with the formula W(CO)6. This complex gave rise to the first example of a dihydrogen complex.Kubas, G. J., Metal Dihydrogen and σ-Bond Complexes, Kluwer Academic/Plenum Publishers: New York, 2001 Like its chromium and molybdenum analogs, this colorless compound is noteworthy as a volatile, air-stable derivative of tungsten in its zero oxidation state. Preparation, properties, and structure Like many metal carbonyls, W(CO)6 is generally prepared by "reductive carbonylation", which involves the reduction of a metal halide with under an atmosphere of carbon monoxide. As described in a 2023 survey of methods "most cost-effective routes for the synthesis of group 6 hexacarbonyls are based on the reduction of the metal chlorides (CrCl3, MoCl5 or WCl6) with magnesium, zinc or aluminium powders... under CO pressures".Another means of preparation involves heating iron pentacarbonyl and WCl6, resulting in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
