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Tetrabromoethane
1,1,2,2-Tetrabromoethane, or simply tetrabromoethane (TBE), is a halogenated hydrocarbon, chemical formula C2H2Br4. Although three bromine atoms may bind to one of the carbon atoms creating 1,1,1,2-tetrabromoethane this is not thermodynamically favorable, so in practice tetrabromoethane is equal to 1,1,2,2-tetrabromoethane, where each carbon atom binds two bromine atoms. Uses It has an unusually high density for an organic compound, near 3 g/mL, due largely to the four bromine atoms.Organic based heavy liquids heavyliquids.com TBE is a at , and is used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromoform
Bromoform is an organic compound with the chemical formula . It is a colorless liquid at room temperature, with a high refractive index and a very high density. Its sweet odor is similar to that of chloroform. It is one of the four haloforms, the others being fluoroform, chloroform, and iodoform. It is a brominated organic solvent. Currently its main use is as a laboratory reagent. It is very slightly soluble in water (one part bromoform in 800 parts water) and is miscible with alcohol, benzene, chloroform, ether, petroleum ether, acetone and oils. Structure The molecule adopts tetrahedral molecular geometry with C3v symmetry. Synthesis Bromoform was discovered in 1832 by Löwig who distilled a mixture of bromal and potassium hydroxide, as analogous to preparation of chloroform from chloral. Bromoform can be prepared by the haloform reaction using acetone and sodium hypobromite, by the electrolysis of potassium bromide in ethanol, or by treating chloroform with aluminium brom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrabromomethane
Carbon tetrabromide, CBr4, also known as tetrabromomethane, is a bromide of carbon. Both names are acceptable under IUPAC nomenclature. Production CBr4 can be obtained by the bromination of methane. The byproducts include other brominated methanes (methyl bromide, dibromomethane and bromoform) and hydrogen bromide. This process is analogous to the chlorination of methane: :Br2 + ''hν'' → 2 Br·; : Br· + CH4 → ·CH3 + HBr. : ·CH3 + Br2 → CH3Br + Br·. : CH3Br + Br· → ·CH2Br + HBr, : ·CH2Br + Br2 → CH2Br2 + Br·, : CH2Br2 + Br· → ·CHBr2 + HBr, : ·CHBr2 + Br2 → CHBr3 + Br·, :CHBr3 + Br· → ·CBr3 + HBr, : ·CBr3 + Br2 → CBr4 + Br· Halogen exchange of carbon tetrachloride with aluminium bromide gives higher yields with aluminium chloride as the byproduct: : 4 AlBr3 + 3 CCl4 → 4 AlCl3 + 3 CBr4 Physical properties Tetrabromomethane has two polymorphs: crystalline II or β below 46.9 °C (320.0 K) and crystalline I or α above 46.9 � ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,1-Dibromoethane
1,1-Dibromoethane is a clear, slightly brown, flammable chemical compound. It is classified as an organobromine compound, and has the chemical formula CHBr and it is a position isomer of 1,2-Dibromoethane, 1,2-dibromoethane. It is commonly seen in industrial chemistry, where it is used as a fuel additive. It is also used as a grain and soil fumigant for insect control. Synthesis 1,1-Dibromoethane is synthesized through addition of hydrogen bromide onto vinyl bromide with absence of peroxide radical. : Safety 1,1-Dibromoethane is considered as a mildly toxic compound, especially with bromines attached as substituents. Bromines on the ethane are strong oxidizing agents. If absorbed through inhalation, 1,1-dibromoethane could potentially cause neuronal effects, tissue damage, and bromism. References {{DEFAULTSORT:Dibromoethane, 1, 1- Bromoalkanes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2-Dibromoethane
1,2-Dibromoethane, also known as ethylene dibromide (EDB), is an organobromine compound with the chemical formula . Although trace amounts occur naturally in the ocean, where it is probably formed by algae and kelp, substantial amounts are produced industrially. It is a dense colorless liquid with a faint, sweet odor, detectable at 10 ppm. It is a widely used and sometimes-controversial fumigant. The combustion of 1,2-dibromoethane produces hydrogen bromide gas that is significantly corrosive. Preparation and use It is produced by the reaction of ethylene gas with bromine, in a classic halogen addition reaction: :CH=CH + Br → BrCH–CHBr Historically, 1,2-dibromoethane was used as a component in anti-knock additives in leaded fuels. It reacts with lead residues to generate volatile lead bromides, thereby preventing fouling of the engine with lead deposits. Pesticide It has been used as a pesticide in soil and on various crops. The applications were initiated after the fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2-Dibromopropane
1,2-Dibromopropane, also known as propylene dibromide, is an organic compound with the formula CHCHBrCHBr. It is the simplest chiral hydrocarbon containing two 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 th ... atoms: References 1,2-Dibromo Propane also known as Propylene bromide is a naturally occurring organic compound. It is part of the Vicinal Dihalide family; it is highly unstable due to both torsional strain and its highly electrophilic nature. Bromoalkanes {{Organohalide-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1,2,3-Tribromopropane
1,2,3-Tribromopropane (TBP) is a toxic organic compound. It is a clear colorless to light yellow liquid Liquid is a state of matter with a definite volume but no fixed shape. Liquids adapt to the shape of their container and are nearly incompressible, maintaining their volume even under pressure. The density of a liquid is usually close to th .... References Bromoalkanes {{Organohalide-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromoform
Bromoform is an organic compound with the chemical formula . It is a colorless liquid at room temperature, with a high refractive index and a very high density. Its sweet odor is similar to that of chloroform. It is one of the four haloforms, the others being fluoroform, chloroform, and iodoform. It is a brominated organic solvent. Currently its main use is as a laboratory reagent. It is very slightly soluble in water (one part bromoform in 800 parts water) and is miscible with alcohol, benzene, chloroform, ether, petroleum ether, acetone and oils. Structure The molecule adopts tetrahedral molecular geometry with C3v symmetry. Synthesis Bromoform was discovered in 1832 by Löwig who distilled a mixture of bromal and potassium hydroxide, as analogous to preparation of chloroform from chloral. Bromoform can be prepared by the haloform reaction using acetone and sodium hypobromite, by the electrolysis of potassium bromide in ethanol, or by treating chloroform with aluminium brom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartz
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The Atom, atoms are linked in a continuous framework of SiO4 silicon–oxygen Tetrahedral molecular geometry, tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of Silicon dioxide, SiO2. Quartz is, therefore, classified structurally as a Silicate mineral#Tectosilicates, framework silicate mineral and compositionally as an oxide mineral. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation from α-quartz to β-quartz takes place abruptly at . Since the transformation is accompanied by a significant change in volume, it can easily induce microfracturing of ceramics or rocks passing through this temperature threshold. There are many different varieties of quartz, several of which are classifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrite
The mineral pyrite ( ), or iron pyrite, also known as fool's gold, is an iron sulfide with the chemical formula Fe S2 (iron (II) disulfide). Pyrite is the most abundant sulfide mineral. Pyrite's metallic luster and pale brass-yellow hue give it a superficial resemblance to gold, hence the well-known nickname of ''fool's gold''. The color has also led to the nicknames ''brass'', ''brazzle'', and ''brazil'', primarily used to refer to pyrite found in coal. The name ''pyrite'' is derived from the Greek (), 'stone or mineral which strikes fire', in turn from (), 'fire'. In ancient Roman times, this name was applied to several types of stone that would create sparks when struck against steel; Pliny the Elder described one of them as being brassy, almost certainly a reference to what is now called pyrite. By Georgius Agricola's time, , the term had become a generic term for all of the sulfide minerals. Pyrite is usually found associated with other sulfides or oxides in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galena
Galena, also called lead glance, is the natural mineral form of lead(II) sulfide (PbS). It is the most important ore of lead and an important source of silver. Galena is one of the most abundant and widely distributed sulfide minerals. It crystallizes in the Cubic (crystal system), cubic crystal system often showing octahedral forms. It is often associated with the minerals sphalerite, calcite and fluorite. As a pure specimen held in the hand, under standard temperature and pressure, galena is insoluble in water and so is almost non-toxic. Handling galena under these specific conditions (such as in a museum or as part of geology instruction) poses practically no risk; however, as lead(II) sulfide is reasonably reactive in a variety of environments, it can be highly toxic if swallowed or inhaled, particularly under prolonged or repeated exposure. Occurrence Galena is the main ore of lead, used since ancient times, since lead can be smelted from galena in an ordinary wood fire. G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphalerite
Sphalerite is a sulfide mineral with the chemical formula . It is the most important ore of zinc. Sphalerite is found in a variety of deposit types, but it is primarily in Sedimentary exhalative deposits, sedimentary exhalative, Carbonate-hosted lead-zinc ore deposits, Mississippi-Valley type, and Volcanogenic massive sulfide ore deposit, volcanogenic massive sulfide deposits. It is found in association with galena, chalcopyrite, pyrite (and other sulfide mineral, sulfides), calcite, dolomite (mineral), dolomite, quartz, rhodochrosite, and fluorite. German geologist Ernst Friedrich Glocker discovered sphalerite in 1847, naming it based on the Greek word ''sphaleros'', meaning "deceiving", due to the difficulty of identifying the mineral. In addition to zinc, sphalerite is an ore of cadmium, gallium, germanium, and indium. Miners have been known to refer to sphalerite as ''zinc blende'', ''black-jack'', and ''ruby blende''. Marmatite is an opaque black variety with a high iron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dolomite (mineral)
Dolomite () is an anhydrous carbonate mineral composed of calcium magnesium carbonate, ideally The term is also used for a sedimentary carbonate rock composed mostly of the mineral dolomite (see Dolomite (rock)). An alternative name sometimes used for the dolomitic rock type is dolostone. History As stated by Nicolas-Théodore de Saussure the mineral dolomite was probably first described by Carl Linnaeus in 1768. In 1791, it was described as a rock by the French natural history, naturalist and geologist Déodat Gratet de Dolomieu (1750–1801), first in buildings of the old city of Rome, and later as samples collected in the County_of_Tyrol, Tyrolean Alps. Nicolas-Théodore de Saussure first named the mineral (after Dolomieu) in March 1792. Properties The mineral dolomite crystallizes in the trigonal, trigonal-rhombohedral system. It forms white, tan, gray, or pink crystals. Dolomite is a double carbonate, having an alternating structural arrangement of calcium and magnesium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
