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Chloroacetone
Chloroacetone is a chemical compound with the formula . At STP it is a colourless liquid with a pungent odour. On exposure to light, it turns to a dark yellow-amber colour. It was used as a tear gas in World War I. Synthesis Chloroacetone may be synthesized from the reaction between chlorine and diketene, or by the chlorination of acetone. Applications Chloroacetone is used to make dye couplers for colour photography, and is an intermediate in chemical manufacturing. It is also used in the Feist-Benary synthesis of furans. *Reaction of phenoxide with chloroacetone gives phenoxyacetone, which is used to make a wide variety of different pharmaceuticals. A catalytic amount of potassium iodide is also necessary to facilitate a Finkelstein reaction. Purification Chloroacetone purchased from commercial suppliers contains 5% impurities including mesityl oxide, which is not removed by distillation. Mesityl oxide can be oxidized using acidified KMnO4 to form a diol (followed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexachloroacetone
Hexachloroacetone is an organic compound with the formula (Cl3C)2CO. It is also called hexachloropropanone or perchloroacetone. Numbers indicating the position of the chlorine-atoms are generally omitted as all the possible positions are substituted with chlorine. It is a colorless liquid, slightly soluble in water. Reactions and uses Hexachloroacetone functions equivalently to trichloroacetyl chloride, i.e. as an trichloroacetylating agent. The main use of hexachloroacetone is as a pesticide. For the use of hexachloroacetone in the preparation of a novel insect repellent see Perkow reaction. The industrial route to hexafluoroacetone involves treatment of hexachloroacetone with HF: :(CCl3)2CO + 6 HF → (CF3)2CO + 6 HCl See also * Chloroacetone Chloroacetone is a chemical compound with the formula . At STP it is a colourless liquid with a pungent odour. On exposure to light, it turns to a dark yellow-amber colour. It was used as a tear gas in World War I. Synthesis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dichloroacetone
Bis(chloromethyl) ketone is a chemical substance with formula . It is a solid, and is used in the making of citric acid. Exposures such as contact or inhalation of bis(chloromethyl) ketone can result in irritation or damage to skin, eyes, throat, lungs, liver and kidneys, as well as headaches and fainting. from the New Jersey Department of Health and Senior Services Legal aspects Bis(chloromethyl) ketone is a substance which is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U.S. |
Chloroform
Chloroform, or trichloromethane, is an organic compound with formula C H 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. 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 air to produce phosgene, dichloromethane, formyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Use Of Poison Gas In World War I
The use of toxic chemicals as weapons dates back thousands of years, but the first large scale use of chemical weapons was during World War I. They were primarily used to demoralize, injure, and kill entrenched defenders, against whom the indiscriminate and generally very slow-moving or static nature of gas clouds would be most effective. The types of weapons employed ranged from disabling chemicals, such as tear gas, to lethal agents like phosgene, chlorine, and mustard gas. This chemical warfare was a major component of the first global war and first total war of the 20th century. The killing capacity of gas was limited, with about 90,000 fatalities from a total of 1.3 million casualties caused by gas attacks. Gas was unlike most other weapons of the period because it was possible to develop countermeasures, such as gas masks. In the later stages of the war, as the use of gas increased, its overall effectiveness diminished. The widespread use of these agents of chemical w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluoroacetone
Fluoroacetone is an organofluorine compound with the chemical formula . In contrast to trifluoroacetone, the compound has one fluorine atom. Under normal conditions, the substance is a colorless liquid. Fluoroacetone is also a highly toxic and flammable compound. Fumes of fluoroacetone can form an explosive mixture with air. Synthesis Fluoroacetone can be obtained by a reaction of triethylamine trihydrofluoride with bromoacetone. Applications Fluoroacetone is used as a catalyst to study the kinetics of the ketone-catalysed decomposition of peroxymonosulfuric acid (Caro's acid). It is also a precursor material for the production of higher fluoroketones. Fluoroacetone has not been used as a lachrymatory substance in contrast to other halogenated acetone derivatives, such as bromoacetone or chloroacetone. See also * Bromoacetone * Chloroacetone * Iodoacetone *Thioacetone Thioacetone is an organosulfur compound belonging to the -thione group called thioketones, with a chemic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Finkelstein Reaction
The Finkelstein reaction named after the German chemist Hans Finkelstein, is an SN2 reaction (Substitution Nucleophilic Bimolecular reaction) that involves the exchange of one halogen atom for another. It is an equilibrium reaction, but the reaction can be driven to completion by exploiting the differential solubility of halide salts, or by using a large excess of the halide salt. :R–X + X′− R–X′ + X− Method The classic Finkelstein reaction entails the conversion of an alkyl chloride or an alkyl bromide to an alkyl iodide by treatment with a solution of sodium iodide in acetone. Sodium iodide is soluble in acetone while sodium chloride and sodium bromide are not. The reaction is driven toward products by mass action due to the precipitation of the poorly soluble NaCl or NaBr. An example involves the conversion of the ethyl ester of 5-bromo valeric acid to the iodide: :EtO2C(CH2)4Br + NaI → EtO2C(CH2) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethanol
Ethanol (abbr. EtOH; also called ethyl alcohol, grain alcohol, drinking alcohol, or simply alcohol) is an organic compound. It is an alcohol with the chemical formula . Its formula can be also written as or (an ethyl group linked to a hydroxyl group). Ethanol is a volatile, 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 sugars by yeasts or via 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 synthesis of organic compounds, and as a fuel source. Ethanol also can be dehydrated to make ethylene, an important chemical feedstock. As of 2006, world production of ethanol was , coming mostly from Brazil and the U.S. Etymology ''Ethanol'' is the systematic name defined by the Interna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lachrymatory Agents , a small vessel of terracotta or glass found in Roman and late Greek tombs, thought to have been used to collect the tears of mourners at funerals
{{disambiguation ...
Lachrymatory or lacrymatory may refer to: * Something that has the effect of ''lachrymation'', causing the secretion of tears * Tear gas, known formally as a ''lachrymatory agent'' or ''lachrymator'' * A lacrymatory A lacrymatory, lachrymatory or lacrimarium (from the Latin ''lacrima'', 'tears, tear') is a small vessel of terracotta or, more frequently, of glass, found in Rome, Roman and late Greece, Greek tombs, and formerly supposed to have been bottles i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organochlorides
An organochloride, organochlorine compound, chlorocarbon, or chlorinated hydrocarbon is an organic compound containing at least one covalently bonded atom of chlorine. The chloroalkane class (alkanes with one or more hydrogens substituted by chlorine) provides common examples. The wide structural variety and divergent chemical properties of organochlorides lead to a broad range of names, applications, and properties. Organochlorine compounds have wide use in many applications, though some are of profound environmental concern, with TCDD being one of the most notorious. Physical and chemical properties Chlorination modifies the physical properties of hydrocarbons in several ways. These compounds are typically denser than water due to the higher atomic weight of chlorine versus hydrogen. Aliphatic organochlorides are often alkylating agents as chlorine can act as a leaving group, which can result in cellular damage. Natural occurrence Many organochlorine compounds have been isolate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bromoacetone
Bromoacetone is an organic compound with the formula . It is a colorless liquid although impure samples appear yellow or even brown. It is a lachrymatory agent and a precursor to other organic compounds. Occurrence in nature Bromoacetone is present (less than 1%) in the essential oil of a seaweed ('' Asparagopsis taxiformis'') from the vicinity of the Hawaiian Islands. Synthesis Bromoacetone is available commercially, sometimes stabilized with magnesium oxide. It was first described in the 19th century, attributed to N. Sokolowsky. Bromoacetone is prepared by combining bromine and acetone, with catalytic acid. As with all ketones, acetone enolizes in the presence of acids or bases. The alpha carbon then undergoes electrophilic substitution with bromine. The main difficulty with this method is over-bromination, resulting in di- and tribrominated products. If a base is present, bromoform is obtained instead, by the haloform reaction. Applications It was used in World War I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UN Number
A UN number (United Nations number) is a four-digit number that identifies hazardous materials, and articles (such as explosives, flammable liquids, oxidizers, toxic liquids, etc.) in the framework of international trade and transport. Some hazardous substances have their own UN numbers (e.g. acrylamide has UN 2074), while sometimes groups of chemicals or products with similar properties receive a common UN number (e.g. flammable liquids, not otherwise specified, have UN 1993). A chemical in its solid state may receive a different UN number than the liquid phase if its hazardous properties differ significantly; substances with different levels of purity (or concentration in solution) may also receive different UN numbers. Hazard identifiers Associated with each UN number is a hazard identifier, which encodes the general hazard class and subdivision (and, in the case of explosives, their compatibility group). If a substance poses several dangers, then subsidiary risk identif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
