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Hydrazine
Hydrazine is an inorganic compound with the chemical formula . It is a simple pnictogen hydride, and is a colourless flammable liquid with an ammonia-like odour. Hydrazine is highly hazardous unless handled in solution as, for example, hydrazine hydrate (). Hydrazine is mainly used as a foaming agent in preparing Polymeric foam, polymer foams, but applications also include its uses as a precursor (chemistry), precursor to pharmaceuticals and agrochemicals, as well as a long-term storable propellant for in-outer space, space spacecraft propulsion. Additionally, hydrazine is used in various rocket propellant, rocket fuels and to prepare the gas precursors used in airbags. Hydrazine is used within both nuclear and conventional electrical power plant steam cycles as an oxygen scavenger to control concentrations of dissolved oxygen in an effort to reduce corrosion. , approximately 120,000 tons of hydrazine hydrate (corresponding to a 64% solution of hydrazine in water by weight) we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrazines
Hydrazines (R2N−NR2) are a class of chemical compounds with two nitrogen atoms linked via a covalent bond and which carry from one up to four alkyl or aryl substituents. Hydrazines can be considered as derivatives of the inorganic hydrazine (H2N−NH2), in which one or more hydrogen atoms have been replaced by hydrocarbon groups. Production * 1,1-dimethylhydrazine, 1,1-Dimethylhydrazine is produced by the reduction of N-Nitrosodimethylamine, ''N''-nitrosodimethylamine.Siegfried Hauptmann: ''Organische Chemie'', 2. durchgesehene Auflage, VEB Deutscher Verlag für Grundstoffindustrie, Leipzig, 1985, S. 522–523, . * The reduction of benzenediazonium chloride with tin(II) chloride and hydrochloric acid provides phenylhydrazine. * 2,4-Dinitrophenylhydrazine is produced by the reaction of 1-chloro-2,4-dinitrobenzene with hydrazine. * Tetraphenylhydrazine is formed by the oxidation of diphenylamine with potassium permanganate in acetone. Classification Hydrazines can b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Peroxide
Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscosity, viscous than Properties of water, water. It is used as an oxidizer, bleaching agent, and antiseptic, usually as a dilute solution (3%–6% by weight) in water for consumer use and in higher concentrations for industrial use. Concentrated hydrogen peroxide, or "high-test peroxide", decomposes explosively when heated and has been used as both a monopropellant and an oxidizer in rocketry. Hydrogen peroxide is a reactive oxygen species and the simplest peroxide, a compound having an oxygen–oxygen single bond. It decomposes slowly into water and elemental oxygen when exposed to light, and rapidly in the presence of organic or reactive compounds. It is typically stored with a Stabilizer (chemistry), stabilizer in a weakly acidic solution in an opaque bottle. Hydrogen peroxide is found in biological systems including the human body. Enzymes that u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonia
Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pungent smell. It is widely used in fertilizers, refrigerants, explosives, cleaning agents, and is a precursor for numeous chemicals. Biologically, it is a common nitrogenous waste, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to fertilisers. Around 70% of ammonia produced industrially is used to make fertilisers in various forms and composition, such as urea and diammonium phosphate. Ammonia in pure form is also applied directly into the soil. Ammonia, either directly or indirectly, is also a building block for the synthesis of many chemicals. In many countries, it is classified as an List of extremely hazardous substances, extremely hazardous substance. Ammonia is toxic, cau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrafluorohydrazine
Tetrafluorohydrazine or perfluorohydrazine, , is a colourless, nonflammable, reactive inorganic gas. It is a fluorinated analog of hydrazine. Synthesis Tetrafluorohydrazine was originally prepared from nitrogen trifluoride using a copper as a fluorine atom acceptor: : A number of F-atom acceptors can be used, including carbon, other metals, and nitric oxide. These reactions exploit the relatively weak N-F bond in NF3. Properties Tetrafluorohydrazine is in equilibrium with its radical monomer nitrogen difluoride. : At room temperature is mostly associated with only 0.7% in the form of at 5mm Hg pressure. When the temperature rises to 225 °C, it mostly dissociates with 99% in the form of . molecule dimensions and angles The energy needed to break the N−N bond in is 20.8 kcal/mol, with an entropy change of 38.6 eu. For comparison, the dissociation energy of the N−N bond is in , in , and in . The enthalpy of formation of (Δf''H''°) is 34.421 kJ/mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ammonia
Ammonia is an inorganic chemical compound of nitrogen and hydrogen with the chemical formula, formula . A Binary compounds of hydrogen, stable binary hydride and the simplest pnictogen hydride, ammonia is a colourless gas with a distinctive pungent smell. It is widely used in fertilizers, refrigerants, explosives, cleaning agents, and is a precursor for numeous chemicals. Biologically, it is a common nitrogenous waste, and it contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to fertilisers. Around 70% of ammonia produced industrially is used to make fertilisers in various forms and composition, such as urea and diammonium phosphate. Ammonia in pure form is also applied directly into the soil. Ammonia, either directly or indirectly, is also a building block for the synthesis of many chemicals. In many countries, it is classified as an List of extremely hazardous substances, extremely hazardous substance. Ammonia is toxic, cau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pnictogen Hydride
Pnictogen hydrides or hydrogen pnictides are binary compounds of hydrogen with pnictogen ( or ; from "to choke" and -gen, "generator") atoms (elements of group 15: nitrogen, phosphorus, arsenic, antimony, bismuth, and moscovium) covalently bonded to hydrogen. Pnictogen trihydrides The simplest series has the chemical formula XH3 (less commonly H3X), with X representing any of the pnictogens. They take on the pyramidal structure (as opposed to the trigonal planar arrangement of the group 13 hydrides), and therefore are polar. These pnictogen trihydrides are generally increasingly unstable and poisonous with heavier elements. Some properties of the pnictogen trihydrides follow: These gases have no smell in pure form, instead gaining it when in contact with air. Ammonia has an infamous, intense odour resembling urine and/or fish, commonly the result of the decomposition of urea. Phosphine smells like fish or garlic, and stibine like rotten eggs, similar to hydrogen sulfide a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrazinium
Hydrazinium is the cation with the formula . This cation has a methylamine-like structure (). It can be derived from hydrazine by protonation (treatment with a strong acid). Hydrazinium is a weak acid with p''K''a = 8.1. Salts of hydrazinium are common reagents in chemistry and are often used in certain industrial processes.Jean-Pierre Schirmann, Paul Bourdauducq "Hydrazine" in ''Ullmann's Encyclopedia of Industrial Chemistry'', Wiley-VCH, Weinheim, 2002. . Notable examples are hydrazinium hydrogensulfate, or , and hydrazinium azide, or . In the common names of such salts, the cation is often called "hydrazine", as in " hydrazine sulfate" for hydrazinium hydrogensulfate. The terms "hydrazinium" and "hydrazine" may also be used for the doubly protonated cation , more properly called hydrazinediium or hydrazinium(2+). This cation has an ethane-like structure (). Salts of this cation include hydrazinediium sulfate and hydrazinediium bis(6-carboxypyridazine-3-carboxylate), .W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triazane
Triazane is an inorganic compound with the chemical formula or . Triazane is the third simplest acyclic azane after ammonia and hydrazine. It can be synthesized from hydrazine but is unstable and cannot be isolated in the free base form, only as salt forms such as triazanium sulfate. Attempts to convert triazanium salts to the free base release only diazene and ammonia. Triazane was first synthesized as a ligand In coordination chemistry, a ligand is an ion or molecule with a functional group that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's el ... of the silver complex ion: tris(μ2-triazane-κ2''N''1,''N''3)disilver(2+). Triazane has also been synthesized in electron-irradiated ammonia ices and detected as a stable gas-phase product after sublimation.Förstel, Maksyutenko, Jones, Sun, Chen, Chang, & Kaiser. "Detection of the Elusive Triazane Molecule () in the Ga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrazene
Tetrazene is a chemical compound with the molecular formula H2NN=NNH2. It is a colorless explosive material. An analogue is the organosilicon derivative (tms)2NN=NN(tms)2 where tms is trimethylsilyl. Isomeric with tetrazine is ammonium azide. Tetrazene explosive, commonly known simply as tetrazene, is used for sensitization of priming compositions. Properties Tetrazene has eleven isomers. The most stable of these is the straight-chain 2-tetrazene (H2N-N=N-NH2), having a standard heat of formation at 301.3 kJ/mol. The eleven isomers can be arranged into three groups: straight-chain tetrazenes, four-membered cyclotetrazane, and three-membered cyclotriazanes. Each straight-chain tetrazene isomer possesses one N=N double bond and two N-N single bonds. Tautomerizations do occur between the isomers. The ionic compound ammonium azide is also a constitutional isomer of tetrazene. Organometallic derivatives A variety of coordination complex A coordination complex is a chemical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Storable Propellant
A propellant (or propellent) is a mass that is expelled or expanded in such a way as to create a thrust or another motive force in accordance with Newton's third law of motion, and "propel" a vehicle, projectile, or fluid payload. In vehicles, the engine that expels the propellant is called a reaction engine. Although technically a propellant is the reaction mass used to create thrust, the term "propellant" is often used to describe a substance which contains both the reaction mass and the fuel that holds the energy used to accelerate the reaction mass. For example, the term "propellant" is often used in chemical rocket design to describe a combined fuel/propellant, although the propellants should not be confused with the fuel that is used by an engine to produce the energy that expels the propellant. Even though the byproducts of substances used as fuel are also often used as a reaction mass to create the thrust, such as with a chemical rocket engine, propellant and fuel are two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emil Fischer
Hermann Emil Louis Fischer (; 9 October 1852 – 15 July 1919) was a German chemist and List of Nobel laureates in Chemistry, 1902 recipient of the Nobel Prize in Chemistry. He discovered the Fischer esterification. He also developed the Fischer projection, a symbolic way of drawing asymmetric carbon atoms. He also hypothesized lock and key mechanism of enzyme action. He never used his first given name, and was known throughout his life simply as Emil Fischer. Early years and career Fischer was born in Euskirchen, near Cologne, the son of Laurenz Fischer, a businessman, and his wife Julie Poensgen. After graduating he wished to study natural sciences, but his father compelled him to work in the family business until determining that his son was unsuitable. Fischer then attended the University of Bonn in 1871, but switched to the University of Strasbourg in 1872. He earned his doctorate in 1874 under Adolf von Baeyer with his study of phthaleins. Fischer remained with Baeyer i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen Scavenger
Oxygen scavengers or oxygen absorbers are added to enclosed packaging to help remove or decrease the level of oxygen in the package. They are used to help maintain product safety and extend shelf life. There are many types of oxygen absorbers available to cover a wide array of applications. The components of an oxygen absorber vary according to intended use, the water activity of the product being preserved, and other factors. Often the oxygen absorber or scavenger is enclosed in a porous sachet or packet but it can also be part of packaging films and structures. Others are part of a polymer structure. Oxygen absorbing chemicals are also commonly added to boiler feedwater used in boiler systems, to reduce corrosion of components within the system. Mechanism The first patent for an oxygen scavenger used an alkaline solution of pyrogallic acid in an air-tight vessel. Modern scavenger sachets use a mixture of iron powder and sodium chloride. Often activated carbon is also incl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
