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Tetracyanomethane
Tetracyanomethane or carbon tetracyanide is a percyanoalkane molecular carbon nitride with formula C(CN)4. The structure can be considered as methane with all hydrogen atoms replaced by cyanide groups. It was first made by Erwin Mayer in 1969. Properties Tetracyanomethane is a solid at room temperature. It decomposes over 160 °C without melting, and although it can be in a dilute vapour, no liquid form is known. The molecules of tetracyanomethane have a tetrahedral symmetry (3''m'' or Td). The molecule has C-C distance of 1.484 Å and C-N distance of 1.161 Å in the gas form. In the solid the C≡N bond shortens to 1.147 Å. The C-C bond has a force constant of 4.86×105 dyn/cm which is slightly greater than the C-Cl bond in carbon tetrachloride, but a fair bit weaker than in the tricyanomethanide ion. At pressures over 7 GPa tetracyanomethane starts to polymerize to form a disorganised covalent network solid. At higher pressure the colour yellows and da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Nitride
In organic chemistry, carbon nitrides are compounds consisting only of carbon and nitrogen atoms. Covalent network compounds * Beta carbon nitride - a solid with a formula β-, which is predicted to be harder than diamond. * Graphitic carbon nitride - g-, with important catalytic and sensor properties. Azafullerenes * Azafullerenes are a class of heterofullerenes in which the element substituting for carbon is nitrogen. Examples include (biazafullerenyl),Hummelen et al, Isolation of the Heterofullerene C59N as Its Dimer (C59N)2, Science 269: 1554-1556 (1995) (diaza 0ullerene), (triaza 0ullerene) and . Cyanofullerenes * Cyanofullerenes are a class of modified fullerenes in which cyano- groups are attached to a fullerene skeleton. These have the formula , where ''n'' takes the values 1 to 9. Cyanogen * Cyanogen - (NCCN) * Isocyanogen - (CNCN) * Diisocyanogen - (CNNC) * Paracyanogen - a cyanogen polymer, * Paraisocyanogen - a cyanogen polymer, Percyanoal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methane
Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The relative abundance of methane on Earth makes it an economically attractive fuel, although capturing and storing it poses technical challenges due to its gaseous state under normal conditions for temperature and pressure. Naturally occurring methane is found both below ground and under the seafloor and is formed by both geological and biological processes. The largest reservoir of methane is under the seafloor in the form of methane clathrates. When methane reaches the surface and the atmosphere, it is known as atmospheric methane. The Earth's atmospheric methane concentration has increased by about 150% since 1750, and it accounts for 20% of the total radiative forcing from all of the long-lived and globally mixed greenhouse gases. It has also been detected on other plane ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanide
Cyanide is a naturally occurring, rapidly acting, toxic chemical that can exist in many different forms. In chemistry, a cyanide () is a chemical compound that contains a functional group. This group, known as the cyano group, consists of a carbon atom triple-bonded to a nitrogen atom. In inorganic cyanides, the cyanide group is present as the anion . Soluble salts such as sodium cyanide (NaCN) and potassium cyanide (KCN) are highly toxic. Hydrocyanic acid, also known as hydrogen cyanide, or HCN, is a highly volatile liquid that is produced on a large scale industrially. It is obtained by acidification of cyanide salts. Organic cyanides are usually called nitriles. In nitriles, the group is linked by a covalent bond to carbon. For example, in acetonitrile (), the cyanide group is bonded to methyl (). Although nitriles generally do not release cyanide ions, the cyanohydrins do and are thus rather toxic. Bonding The cyanide ion is isoelectronic with carbon monoxide a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erwin Mayer
Erwin may refer to: People Given name * Erwin Chargaff (1905–2002), Austrian biochemist * Erwin Dold (1919–2012), German concentration camp commandant in World War 2 * Erwin Hauer (1926–2017), Austrian-born American sculptor * Egon Erwin Kisch (1885–1948), Czechoslovak writer and journalist * Erwin Emata (born 1973), Filipino mountain climber * Erwin James (born 1957), British writer and journalist * Erwin Klein (died 1992), American table tennis player * Erwin Koeman (born 1961), Dutch footballer and coach * Erwin Kramer (1902–1979), East German politician * Erwin Kreyszig (1922–2008), American academic * Erwin Neutzsky-Wulff (born 1949), Danish author and philosopher * Erwin Osen (1891–1970), Austrian mime artist * Erwin Panofsky (1892-1968), German-Jewish art historian * Erwin Ramírez (born 1971), Ecuadorian football player * Erwin Rommel (1891–1944), German field marshal of World War II * Erwin Rösener (1902–1946), German Nazi SS officer executed for war cri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrahedral
In geometry, a tetrahedron (plural: tetrahedra or tetrahedrons), also known as a triangular pyramid, is a polyhedron composed of four triangular faces, six straight edges, and four vertex corners. The tetrahedron is the simplest of all the ordinary convex polyhedra and the only one that has fewer than 5 faces. The tetrahedron is the three-dimensional case of the more general concept of a Euclidean simplex, and may thus also be called a 3-simplex. The tetrahedron is one kind of pyramid, which is a polyhedron with a flat polygon base and triangular faces connecting the base to a common point. In the case of a tetrahedron the base is a triangle (any of the four faces can be considered the base), so a tetrahedron is also known as a "triangular pyramid". Like all convex polyhedra, a tetrahedron can be folded from a single sheet of paper. It has two such nets. For any tetrahedron there exists a sphere (called the circumsphere) on which all four vertices lie, and another sphere ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbon Tetrachloride
Carbon tetrachloride, also known by many other names (such as tetrachloromethane, also IUPAC nomenclature of inorganic chemistry, recognised by the IUPAC, carbon tet in the cleaning industry, Halon-104 in firefighting, and Refrigerant-10 in HVACR) is an organic compound with the chemical formula CCl4. It is a colourless liquid with a "sweet" smell that can be detected at low levels. It is practically incombustible at lower temperatures. It was formerly widely used in fire extinguishers, as a precursor to refrigerants and as a cleaning agent, but has since been phased out because of environmental and safety concerns. Exposure to high concentrations of carbon tetrachloride (including vapor) can affect the central nervous system and degenerate the liver and kidneys. Prolonged exposure can be fatal. Properties In the carbon tetrachloride molecule, four chlorine atoms are positioned symmetrically as corners in a tetrahedron, tetrahedral configuration joined to a central carbon atom by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tricyanomethanide
Cyanoform (tricyanomethane) is a cyanocarbon and derivative of methane with three cyano groups. For many years, chemists have been unable to isolate this compound as a neat, free acid. However, in September 2015, reports surfaced of a successful isolation. Properties Dilute solutions of this acid, as well as its salts, have long been well known. Cyanoform ranks as one of the most acidic of the carbon acids with an estimated pKa of -5.1 in water and measured pKa of 5.1 in acetonitrile. The reaction of sulfuric acid with sodium tricyanomethanide in water (a reaction first tried by H. Schmidtmann in 1896 with inconclusive results) is reported to result in the formation of the hydrate or the formation of (''Z'')-3-amino-2-cyano-3-hydroxyacrylamide, , depending on the precise conditions. The reaction of HCl gas with sodium tricyanomethanide dissolved in THF is reported to yield 1-chloro-1-amino-2,2-dicyanoethylene () and its tautomer. Isolation In September 2015 cyanoform was s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanogen Chloride
Cyanogen chloride is a highly toxic chemical compound with the formula CNCl. This linear, triatomic pseudohalogen is an easily condensed colorless gas. More commonly encountered in the laboratory is the related compound cyanogen bromide, a room-temperature solid that is widely used in biochemical analysis and preparation. Synthesis, basic properties, structure Cyanogen chloride is a molecule with the connectivity . Carbon and chlorine are linked by a single bond, and carbon and nitrogen by a triple bond. It is a linear molecule, as are the related cyanogen halides (NCF, NCBr, NCI). Cyanogen chloride is produced by the oxidation of sodium cyanide with chlorine. This reaction proceeds via the intermediate cyanogen (). :NaCN + Cl2 -> ClCN + NaCl The compound trimerizes in the presence of acid to the heterocycle called cyanuric chloride. Cyanogen chloride is slowly hydrolyzed by water at neutral pH to release cyanate and chloride ions: :ClCN + H2O -> NCO- + Cl- + 2H+ Applicatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyanate
Cyanate is an anion with the structural formula , usually written . It also refers to any salt containing it, such as ammonium cyanate. It is an isomer of the much less stable fulminate anion .William R. Martin and David W. Ball (2019): "Small organic fulminates as high energy materials. Fulminates of acetylene, ethylene, and allene". ''Journal of Energetic Materials'', volume 31, issue 7, pages 70-79. A cyanate ester is an organic compound containing the cyanate group. The cyanate ion is an ambidentate ligand, forming complexes with a metal ion in which either the nitrogen or oxygen atom may be the electron-pair donor. It can also act as a bridging ligand. Cyanate ion The three atoms in a cyanate ion lie on a straight line, giving the ion a linear structure. The electronic structure is described most simply as : :Ö̤−C≡N: with a single C−O bond and a triple C≡N bond. The infrared spectrum of a cyanate salt has a band at ca. 2096 cm−1; such a high frequen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tricyanomethane
Cyanoform (tricyanomethane) is a cyanocarbon and derivative of methane with three cyano groups. For many years, chemists have been unable to isolate this compound as a neat, free acid. However, in September 2015, reports surfaced of a successful isolation. Properties Dilute solutions of this acid, as well as its salts, have long been well known. Cyanoform ranks as one of the most acidic of the carbon acids with an estimated pKa of -5.1 in water and measured pKa of 5.1 in acetonitrile. The reaction of sulfuric acid with sodium tricyanomethanide in water (a reaction first tried by H. Schmidtmann in 1896 with inconclusive results) is reported to result in the formation of the hydrate or the formation of (''Z'')-3-amino-2-cyano-3-hydroxyacrylamide, , depending on the precise conditions. The reaction of HCl gas with sodium tricyanomethanide dissolved in THF is reported to yield 1-chloro-1-amino-2,2-dicyanoethylene () and its tautomer. Isolation In September 2015 cyanoform was s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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