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1,1-Dibromoethane
1,1-Dibromoethane is a clear, slightly brown, flammable chemical compound. It is classified as the 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 mild 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] |
1,1-dibromoethane
1,1-Dibromoethane is a clear, slightly brown, flammable chemical compound. It is classified as the 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 mild 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] |
Dibromomethane
Preparation Dibromomethane is prepared commercially from dichloromethane via bromochloromethane: :6 CH2Cl2 + 3 Br2 + 2 Al → 6 CH2BrCl + 2 AlCl3 :CH2Cl2 + HBr → CH2BrCl + HCl The latter route requires aluminium trichloride as a catalyst. The bromochloromethane product from either reaction can further react in a similar manner: :6 CH2BrCl + 3 Br2 + 2 Al → 6 CH2Br2 + 2 AlCl3 :CH2BrCl + HBr → CH2Br2 + HCl In the laboratory, it is prepared from bromoform: :CHBr3 + Na3AsO3 + NaOH → CH2Br2 + Na3AsO4 + NaBr using sodium arsenite and sodium hydroxide. Another way is to prepare it from diiodomethane and bromine. Uses Dibromomethane is used as a solvent, gauge fluid, and in organic synthesis (often as 1H-NMR internal standard). It is a convenient agent for converting catechols to their methylenedioxy derivatives. Natural occurrence It is naturally produced by marine algae and liberated to the oceans. Releasing on soil causes it to evaporate and leach into ... [...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 with the symbol Br and atomic number 35. It is the third-lightest element in group 17 of the periodic table (halogens) and is a volatile red-brown liquid at room temperature that evaporates readily to form a simila ... 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-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 formed probably by algae and kelp, it is mainly synthetic. It is a dense colorless liquid with a faint sweet odor, detectable at 10 ppm, 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 forced retirement of 1,2-dibrom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrabromomethane
Tetrabromomethane, CBr4, also known as carbon tetrabromide, is a carbon bromide. Both names are acceptable under IUPAC nomenclature. 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 °C. Monoclinic polymorph has space group ''C2/c'' with lattice constants: ''a'' = 20.9, ''b'' = 12.1, ''c'' = 21.2 (.10−1 nm), β = 110.5°.F. Brezina, J. Mollin, R. Pastorek, Z. Sindelar. ''Chemicke tabulky anorganickych sloucenin'' (''Chemical tables of inorganic compounds''). SNTL, 1986. Bond energy of C-Br is 235 kJ.mol−1.N. N. Greenwood, A. Earnshaw. ''Chemie prvku'' (''Chemistry of the Elements''). Informatorium, Prague, 1993. Due to its symmetrically substituted tetrahedral structure, its dipole moment is 0 Debye. Critical temperature is 439 °C (712 K) and critical pressure is 4.26 MPa. Plastic crystallinity The high temperature α phase is known as a plastic crystal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromoform
Bromoform (CHBr3) is a brominated organic solvent, colorless liquid at room temperature, with a high refractive index, very high density, and sweet odor is similar to that of chloroform. It is one of the four haloforms, the others being fluoroform, chloroform, and iodoform. 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 bromide. Currently its main use is as a laboratory reagent. Structure The molecule adopts tetrahedral molecular geometry with C3v symmetry. Uses Only small quantities of bromoform are currently produced industrially in the United States. In the past, it was used as a solvent, sedative and flame retardant, but now it is mainly used as a laboratory reagent, for example as an extraction solvent. Bromoform also has medical uses; injections of bromoform are sometimes used instead of epinephrine to treat severe asthma cases. Bromo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrabromoethane
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 to separate |
Chloroform
Chloroform, or trichloromethane, is an organic compound with chemical formula, formula Carbon, CHydrogen, HChlorine, Cl3 and a common organic solvent. It is a colorless, strong-smelling, dense liquid produced on a large scale as a precursor to PTFE. It is also a precursor to various refrigerants. It is trihalomethane. It is a powerful anesthetic, euphoriant, anxiolytic, and sedative when inhaled or ingested. Structure The molecule adopts a tetrahedral molecular geometry with C3v symmetry group, symmetry. Natural occurrence The total global flux of chloroform through the environment is approximately tonnes per year, and about 90% of emissions are natural in origin. Many kinds of seaweed produce chloroform, and fungi are believed to produce chloroform in soil. Abiotic processes are also believed to contribute to natural chloroform productions in soils although the mechanism is still unclear. Chloroform volatilizes readily from soil and surface water and undergoes degradation in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benzene
Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each. Because it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon. Benzene is a natural constituent of petroleum and is one of the elementary petrochemicals. Due to the cyclic continuous pi bonds between the carbon atoms, benzene is classed as an aromatic hydrocarbon. Benzene is a colorless and highly flammable liquid with a sweet smell, and is partially responsible for the aroma of gasoline. It is used primarily as a precursor to the manufacture of chemicals with more complex structure, such as ethylbenzene and cumene, of which billions of kilograms are produced annually. Although benzene is a major industrial chemical, it finds limited use in consumer items because of its toxicity. History Discovery The word "''benzene''" derives from "''gum benzoin''" (benzoin res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetone
Acetone (2-propanone or dimethyl ketone), is an organic compound with the formula . It is the simplest and smallest ketone (). It is a colorless, highly volatile and flammable liquid with a characteristic pungent odour. Acetone is miscible with water and serves as an important organic solvent in its own right, in industry, home, and laboratory. About 6.7 million tonnes were produced worldwide in 2010, mainly for use as a solvent and production of methyl methacrylate (and from that PMMA) as well as bisphenol A.Acetone World Petrochemicals report, January 2010Stylianos Sifniades, Alan B. Levy, "Acetone" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. It is a common building block in |
Ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an Alcohol (chemistry), alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a hydroxyl group). Ethanol is a Volatility (chemistry), volatile, Combustibility and flammability, flammable, colorless liquid with a characteristic wine-like odor and pungent taste. It is a psychoactive recreational drug, the active ingredient in alcoholic drinks. Ethanol is naturally produced by the fermentation process of Carbohydrate, sugars by yeasts or via Petrochemistry, petrochemical processes such as ethylene hydration. It has medical applications as an antiseptic and disinfectant. It is used as a chemical solvent and in the Chemical synthesis, synthesis of organic compounds, and as a Alcohol fuel, fuel source. Ethanol also can be dehydrated to make ethylene, an important chemical feedstock. As of 2006, world produ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
National Center For Biotechnology Information
The National Center for Biotechnology Information (NCBI) is part of the United States National Library of Medicine (NLM), a branch of the National Institutes of Health (NIH). It is approved and funded by the government of the United States. The NCBI is located in Bethesda, Maryland, and was founded in 1988 through legislation sponsored by US Congressman Claude Pepper. The NCBI houses a series of databases relevant to biotechnology and biomedicine and is an important resource for bioinformatics tools and services. Major databases include GenBank for DNA sequences and PubMed, a bibliographic database for biomedical literature. Other databases include the NCBI Epigenomics database. All these databases are available online through the Entrez search engine. NCBI was directed by David Lipman, one of the original authors of the BLAST sequence alignment program and a widely respected figure in bioinformatics. GenBank NCBI had responsibility for making available the GenBank DNA seque ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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