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1,2-difluoroethylene
1,2-Difluoroethylene, also known as 1,2-difluoroethene, is an organofluoride with the molecular formula CHF. It can exist as either of two geometric isomers, ''cis''-1,2-difluoroethylene or ''trans''-1,2-difluoroethylene. It is regarded as a hazardous chemical for being toxic by inhalation, and a volatile chemical, and it causes irritation when it comes into contact with the skin and mucous membranes. ''E-Z'' relative stability For most 1,2-disubstituted compounds that exhibit ''cis''–''trans'' isomerism, the ''trans'' (''E'') isomer is more stable than the ''cis'' (''Z'') isomer. However, 1,2-difluoroethylene has the opposite situation, with the ''cis'' more stable than the ''trans'' by 0.9 kcal/mol. See also * 1,1-Difluoroethylene *Perfluoroisobutene Perfluoroisobutene (PFIB) is the perfluorocarbon with the formula . Classified as a perfluoroalkene, it is the fluorinated counterpart of the hydrocarbon isobutene. This colorless gas is notable for its high toxicity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cis–trans Isomerism
''Cis''–''trans'' isomerism, also known as geometric isomerism, describes certain arrangements of atoms within molecules. The prefixes "''cis''" and "''trans''" are from Latin: "this side of" and "the other side of", respectively. In the context of chemistry, ''cis'' indicates that the functional groups (substituents) are on the same side of some plane, while ''trans'' conveys that they are on opposing (transverse) sides. ''Cis''–''trans'' isomers are stereoisomers, that is, pairs of molecules which have the same formula but whose functional groups are in different orientations in three-dimensional space. ''Cis'' and ''trans'' isomers occur both in organic molecules and in inorganic coordination complexes. ''Cis'' and ''trans'' descriptors are not used for cases of conformational isomerism where the two geometric forms easily interconvert, such as most open-chain single-bonded structures; instead, the terms "''syn''" and "''anti''" are used. According to IUPAC, "geome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organofluoride
Organofluorine chemistry describes the chemistry of organofluorine compounds, organic compounds that contain a carbon–fluorine bond. Organofluorine compounds find diverse applications ranging from oil and water repellents to pharmaceuticals, refrigerants, and reagents in catalysis. In addition to these applications, some organofluorine compounds are pollutants because of their contributions to ozone depletion, global warming, bioaccumulation, and toxicity. The area of organofluorine chemistry often requires special techniques associated with the handling of fluorinating agents. The carbon–fluorine bond Fluorine has several distinctive differences from all other substituents encountered in organic molecules. As a result, the physical and chemical properties of organofluorines can be distinctive in comparison to other organohalogens. # The carbon–fluorine bond is one of the strongest in organic chemistry (an average bond energy around 480 kJ/mol). This is significantly st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geometric Isomerism
Geometry (; ) is a branch of mathematics concerned with properties of space such as the distance, shape, size, and relative position of figures. Geometry is, along with arithmetic, one of the oldest branches of mathematics. A mathematician who works in the field of geometry is called a '' geometer''. Until the 19th century, geometry was almost exclusively devoted to Euclidean geometry, which includes the notions of point, line, plane, distance, angle, surface, and curve, as fundamental concepts. Originally developed to model the physical world, geometry has applications in almost all sciences, and also in art, architecture, and other activities that are related to graphics. Geometry also has applications in areas of mathematics that are apparently unrelated. For example, methods of algebraic geometry are fundamental in Wiles's proof of Fermat's Last Theorem, a problem that was stated in terms of elementary arithmetic, and remained unsolved for several centuries. During t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hazardous Chemical
Dangerous goods are substances that are a risk to health, safety, property or the environment during transport. Certain dangerous goods that pose risks even when not being transported are known as hazardous materials ( syllabically abbreviated as HAZMAT or hazmat). An example of dangerous goods is hazardous waste which is waste that threatens public health or the environment. Hazardous materials are often subject to chemical regulations. Hazmat teams are personnel specially trained to handle dangerous goods, which include materials that are radioactive, flammable, explosive, corrosive, oxidizing, asphyxiating, biohazardous, toxic, poisonous, pathogenic, or allergenic. Also included are physical conditions such as compressed gases and liquids or hot materials, including all goods containing such materials or chemicals, or may have other characteristics that render them hazardous in specific circumstances. Dangerous goods are often indicated by diamond-shaped signage on the it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perfluoroisobutene
Perfluoroisobutene (PFIB) is the perfluorocarbon with the formula . Classified as a perfluoroalkene, it is the fluorinated counterpart of the hydrocarbon isobutene. This colorless gas is notable for its high toxicity. Production and reactions PFIB is one product of pyrolysis of polytetrafluoroethylene (PTFE). Tetrafluoroethylene thermally dimerizes to octafluorocyclobutane, which above 600 °C degrades to hexafluoropropylene and PFIB. Perfluoroisobutene is highly reactive toward nucleophiles, e.g. methanol. It alsoforms addition compounds with thiols, and it is this reactivity that may be related to its toxicity. It hydrolyzes readily to give the relatively innocuous (CF3)2CHCO2H, which readily decarboxylates to give hexafluoropropane. Oxidation of HFIB with potassium permanganate gives hexafluoroacetone. Safety Perfluoroisobutene is highly toxic with an LCt = 880 mg⋅min⋅m−3 (mice). It is a Schedule 2 substance of the Chemical Weapons Convention. Its toxi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
