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Scandium Tribromide
Scandium bromide, or ScBr3, is a trihalide, hygroscopic, water-soluble chemical compound of scandium and bromine. Preparation and properties ScBr3 is produced through the burning of scandium in bromine gas. :2 Sc(s) + 3 Br2(g) → 2 ScBr3(s) Scandium bromide can also be prepared by reacting excess hydrobromic acid with scandium oxide, and the hexahydrate can be crystallized from the solution. The thermal decomposition of hexahydrate can only yield scandium oxybromide (ScOBr) and scandium oxide. The anhydrous form can be produced by the reaction of bromine, scandium oxide and graphite in nitrogen gas. Heating reaction between ammonium bromide Ammonium bromide, NH4Br, is the ammonium salt of hydrobromic acid. The chemical crystallizes in colorless prisms, possessing a saline taste; it sublimes on heating and is easily soluble in water. On exposure to air it gradually assumes a yellow ... and scandium oxide or scandium bromide hexahydrate, through (NH4)3ScBr6 intermediate, d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anhydrous
A substance is anhydrous if it contains no water. Many processes in chemistry can be impeded by the presence of water; therefore, it is important that water-free reagents and techniques are used. In practice, however, it is very difficult to achieve perfect dryness; anhydrous compounds gradually absorb water from the atmosphere so they must be stored carefully. Solids Many salts and solids can be dried using heat, or under vacuum. Desiccators can also be used to store reagents in dry conditions. Common desiccants include phosphorus pentoxide and silica gel. Chemists may also require dry glassware for sensitive reactions. This can be achieved by drying glassware in an oven, by flame, or under vacuum. Dry solids can be produced by freeze-drying, which is also known as lyophilization. Liquids or solvents In many cases, the presence of water can prevent a reaction from happening, or cause undesirable products to form. To prevent this, anhydrous solvents must be used when perform ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromine
Bromine is a chemical element; it has chemical symbol, symbol Br and atomic number 35. It is a volatile red-brown liquid at room temperature that evaporates readily to form a similarly coloured vapour. Its properties are intermediate between those of chlorine and iodine. Isolated independently by two chemists, Carl Jacob Löwig (in 1825) and Antoine Jérôme Balard (in 1826), its name was derived , referring to its sharp and pungent smell. Elemental bromine is very reactive and thus does not occur as a free element in nature. Instead, it can be isolated from colourless soluble crystalline mineral halide Ionic salt, salts analogous to table salt, a property it shares with the other halogens. While it is rather rare in the Earth's crust, the high solubility of the bromide ion (Br) has caused its Bromine cycle, accumulation in the oceans. Commercially the element is easily extracted from brine evaporation ponds, mostly in the United States and Israel. The mass of bromine in the oce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromides
A bromide ion is the negatively charged form (Br−) of the element bromine, a member of the halogens group on the periodic table. Most bromides are colorless. Bromides have many practical roles, being found in anticonvulsants, flame-retardant materials, and cell stains. Although uncommon, chronic toxicity from bromide can result in bromism, a syndrome with multiple neurological symptoms. Bromide toxicity can also cause a type of skin eruption, see potassium bromide. The bromide ion has an ionic radius of 196 pm. Natural occurrence Bromide is present in typical seawater (35 PSU) with a concentration of around 65 mg/L, which is about 0.2% of all dissolved salts. Seafood and deep sea plants generally have higher levels than land-derived foods. Bromargyrite—natural, crystalline silver bromide—is the most common bromide mineral known but is still very rare. In addition to silver, bromine is also in minerals combined with mercury and copper. Formation and re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solid-state Chemistry
Solid-state chemistry, also sometimes referred as materials chemistry, is the study of the Chemical synthesis, synthesis, structure, and properties of solid phase materials. It therefore has a strong overlap with solid-state physics, mineralogy, crystallography, ceramics, metallurgy, thermodynamics, materials science and electronics with a focus on the synthesis of novel materials and their characterization. A diverse range of synthetic techniques, such as the ceramic method and Chemical vapor deposition, chemical vapour depostion, make solid-state materials. Solids can be classified as crystalline or amorphous on basis of the nature of order present in the arrangement of their constituent particles. Their elemental compositions, microstructures, and physical properties can be characterized through a variety of analytical methods. History Because of its direct relevance to products of commerce, solid state inorganic chemistry has been strongly driven by technology. Progress in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonium Bromide
Ammonium bromide, NH4Br, is the ammonium salt of hydrobromic acid. The chemical crystallizes in colorless prisms, possessing a saline taste; it sublimes on heating and is easily soluble in water. On exposure to air it gradually assumes a yellow color because of the oxidation of bromide (Br−) to bromine (Br2). Preparation Ammonium bromide can be prepared by the direct action of hydrogen bromide on ammonia. : NH3 + HBr → NH4Br It can also be prepared by the reaction of ammonia with iron(II) bromide or iron(III) bromide, which may be obtained by passing aqueous bromine solution over iron filings. : 2 NH3 + FeBr2 + 2 H2O → 2 NH4Br + Fe(OH)2 Reactions Ammonium bromide is a weak acid with a p''K''a of approximately 9 in water. It is an acid salt because the ammonium ion hydrolyzes slightly in water. Ammonium bromide is a strong electrolyte when put in water: :NH4Br(s) → (aq) + Br−(aq) Ammonium bromide decomposes to ammonia and hydrogen bromide when heated at elev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen
Nitrogen is a chemical element; it has Symbol (chemistry), symbol N and atomic number 7. Nitrogen is a Nonmetal (chemistry), nonmetal and the lightest member of pnictogen, group 15 of the periodic table, often called the Pnictogen, pnictogens. It is a common element in the universe, estimated at Abundance of the chemical elements, seventh in total abundance in the Milky Way and the Solar System. At standard temperature and pressure, two atoms of the element chemical bond, bond to form N2, a colourless and odourless diatomic molecule, diatomic gas. N2 forms about 78% of Atmosphere of Earth, Earth's atmosphere, making it the most abundant chemical species in air. Because of the volatility of nitrogen compounds, nitrogen is relatively rare in the solid parts of the Earth. It was first discovered and isolated by Scottish physician Daniel Rutherford in 1772 and independently by Carl Wilhelm Scheele and Henry Cavendish at about the same time. The name was suggested by French chemist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graphite
Graphite () is a Crystallinity, crystalline allotrope (form) of the element carbon. It consists of many stacked Layered materials, layers of graphene, typically in excess of hundreds of layers. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on a large scale (1.3million metric tons per year in 2022) for uses in many critical industries including refractories (50%), lithium-ion batteries (18%), foundries (10%), and lubricants (5%), among others (17%). Graphite converts to diamond under extremely high pressure and temperature. Graphite's low cost, thermal and chemical inertness and characteristic conductivity of heat and electricity finds numerous applications in high energy and high temperature processes. Types and varieties Graphite can occur naturally or be produced synthetically. Natural graphite is obtained from naturally occurring geologic deposits and synthetic graphite is produced t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scandium Oxybromide
Scandium is a chemical element; it has symbol Sc and atomic number 21. It is a silvery-white metallic d-block element. Historically, it has been classified as a rare-earth element, together with yttrium and the lanthanides. It was discovered in 1879 by spectral analysis of the minerals euxenite and gadolinite from Scandinavia. Scandium is present in most of the deposits of rare-earth and uranium compounds, but it is extracted from these ores in only a few mines worldwide. Because of the low availability and difficulties in the preparation of metallic scandium, which was first done in 1937, applications for scandium were not developed until the 1970s, when the positive effects of scandium on aluminium alloys were discovered. Its use in such alloys remains its only major application. The global trade of scandium oxide is 15–20 tonnes per year. The properties of scandium compounds are intermediate between those of aluminium and yttrium. A diagonal relationship exists between the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scandium Oxide
Scandium(III) oxide or scandia is a inorganic compound with formula scandium, Sc2oxygen, O3. It is one of several oxides of rare earth elements with a high melting point. It is used in the preparation of other scandium compounds as well as in high-temperature systems (for its resistance to heat and thermal shock), electronic ceramics, and glass composition (as a helper material). Structure and physical properties Scandium(III) oxide adopts a Cubic crystal system, cubic crystal structure (point group: tetrahedral (Th), space group: Ia) containing 6-coordinate metal centres. Powder diffraction analysis shows Sc−O bond distances of 2.159–2.071 Å. Scandium oxide is an insulator with a band gap of 6.0 eV. Production Scandium oxide is the primary form of refined scandium produced by the mining industry. Scandium-rich ores, such as thortveitite (Sc,Y)2(Si2O7) and kolbeckite ScPO4·2H2O are rare, however trace amounts of scandium are present in many other minerals. Scan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrobromic Acid
Hydrobromic acid is an aqueous solution of hydrogen bromide. It is a strong acid formed by dissolving the diatomic molecule hydrogen bromide (HBr) in water. "Constant boiling" hydrobromic acid is an aqueous solution that distills at and contains 47.6% HBr by mass, which is 8.77 mol/L. Hydrobromic acid is one of the strongest mineral acids known. Uses Hydrobromic acid is mainly used for the production of inorganic bromides, especially the bromides of zinc, calcium, and sodium. It is a useful reagent for generating organobromine compounds. Certain ethers are cleaved with HBr. It also catalyzes alkylation reactions and the extraction of certain ores. Industrially significant organic compounds prepared from hydrobromic acid include allyl bromide, tetrabromobis(phenol), and bromoacetic acid. HBr participates in anti-Markovnikov hydrohalogenation of alkenes in the presence of peroxides. The resulting 1-bromoalkanes are versatile alkylating agents, giving rise to fatty amines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scandium
Scandium is a chemical element; it has Symbol (chemistry), symbol Sc and atomic number 21. It is a silvery-white metallic d-block, d-block element. Historically, it has been classified as a rare-earth element, together with yttrium and the lanthanides. It was discovered in 1879 by spectral analysis of the minerals euxenite and gadolinite from Scandinavia. Scandium is present in most of the deposits of rare-earth and uranium compounds, but it is extracted from these ores in only a few mines worldwide. Because of the low availability and difficulties in the preparation of metallic scandium, which was first done in 1937, applications for scandium were not developed until the 1970s, when the positive effects of scandium on aluminium alloys were discovered. Its use in such alloys remains its only major application. The global trade of scandium oxide is 15–20 tonnes per year. The properties of scandium compounds are intermediate between those of aluminium and yttrium. A diagonal rela ... [...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] |
