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Trinitromethane
Trinitromethane, also referred to as nitroform, is a nitroalkane and oxidizer with chemical formula HC(NO2)3. It was first obtained in 1857 as the ammonium salt by the Russian chemist Leon Nikolaevich Shishkov (1830–1908). In 1900, it was discovered that nitroform can be produced by the reaction of acetylene with anhydrous nitric acid. This method went on to become the industrial process of choice during the 20th century. In the laboratory, nitroform can also be produced by hydrolysis of tetranitromethane under mild basic conditions. Acidity Trinitromethane as a neutral molecule is colorless. It is highly acidic, easily forming an intensely yellow anion, (NO2)3C−. The p''K''a of trinitromethane has been measured at 0.17 ± 0.02 at 20 °C, which is remarkably acidic for a methane derivative. Trinitromethane easily dissolves in water to form an acidic yellow solution. There is some evidence that the anion, which obeys the 4''n''+2 Hückel rule Hückel or Huckel may refer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetranitromethane
Tetranitromethane or TNM is an organic oxidizer with chemical formula . Its chemical structure consists of four nitro groups attached to one carbon atom. In 1857 it was first synthesised by the reaction of sodium cyanoacetamide with nitric acid. Uses It has been investigated for use as an oxidizer in bipropellant rockets; however, its high melting point makes it unsuitable. Highly purified tetranitromethane cannot be made to explode, but its sensitivity is increased dramatically by oxidizable contaminants, such as anti-freezing additives. This makes it effectively unusable as a propellant. In the laboratory it is used as a reagent for the detection of double bonds in organic compounds and as a nitrating reagent. It has also found use as an additive to diesel fuel to increase the cetane number. Preparation TNM is a pale yellow liquid that can be prepared in the laboratory by the nitration of acetic anhydride with anhydrous nitric acid (Chattaway's method). This method was attemp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetranitromethane
Tetranitromethane or TNM is an organic oxidizer with chemical formula . Its chemical structure consists of four nitro groups attached to one carbon atom. In 1857 it was first synthesised by the reaction of sodium cyanoacetamide with nitric acid. Uses It has been investigated for use as an oxidizer in bipropellant rockets; however, its high melting point makes it unsuitable. Highly purified tetranitromethane cannot be made to explode, but its sensitivity is increased dramatically by oxidizable contaminants, such as anti-freezing additives. This makes it effectively unusable as a propellant. In the laboratory it is used as a reagent for the detection of double bonds in organic compounds and as a nitrating reagent. It has also found use as an additive to diesel fuel to increase the cetane number. Preparation TNM is a pale yellow liquid that can be prepared in the laboratory by the nitration of acetic anhydride with anhydrous nitric acid (Chattaway's method). This method was attemp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrazinium Nitroformate
Hydrazinium nitroformate (HNF) is a salt of hydrazine and nitroform (trinitromethane). It has the molecular formula and is soluble in most solvents. Hydrazinium nitroformate is an energetic oxidizer. Research is being conducted at the European Space Agency to investigate its use in solid rocket propellants. It tends to produce propellants which burn very rapidly and with very high combustion efficiency. Its high energy leads to high specific impulse Specific impulse (usually abbreviated ) is a measure of how efficiently a reaction mass engine (a rocket using propellant or a jet engine using fuel) creates thrust. For engines whose reaction mass is only the fuel they carry, specific impulse i ... propellants. It is currently an expensive research chemical available only in limited quantities. A disadvantage of HNF is its limited thermal stability. References {{reflist Rocket fuels Hydrazinium compounds Nitroalkanes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexanitroethane
Hexanitroethane (HNE) is an organic compound with chemical formula C2N6O12 or (O2N)3C-C(NO2)3. It is a solid matter with a melting point of 135 °C. Hexanitroethane is used in some pyrotechnic compositions as a nitrogen-rich oxidizer, e.g. in some decoy flare compositions and some propellants. Like hexanitrobenzene, HNE is investigated as a gas source for explosively pumped gas dynamic laser. A composition of HNE as oxidizer with boron as fuel is being investigated as a new explosive. Preparation The first synthesis was described by Wilhelm Will in 1914, using the reaction between the potassium salt of tetranitroethane with nitric acid. :C2(NO2)4K2 + 4 HNO3 → C2(NO2)6 + 2 KNO3 + 2 H2O A practicable method for industrial use starts with furfural, which first undergoes oxidative ring-opening by bromine to mucobromic acid. In the following step, mucobromic acid is reacted with potassium nitrite at just below room temperature to form the dipotassium salt of 2,3,3-trinitropro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitroalkane
In organic chemistry, nitro compounds are organic compounds that contain one or more nitro functional groups (). The nitro group is one of the most common explosophores (functional group that makes a compound explosive) used globally. The nitro group is also strongly electron-withdrawing. Because of this property, bonds alpha (adjacent) to the nitro group can be acidic. For similar reasons, the presence of nitro groups in aromatic compounds retards electrophilic aromatic substitution but facilitates nucleophilic aromatic substitution. Nitro groups are rarely found in nature. They are almost invariably produced by nitration reactions starting with nitric acid. Synthesis Preparation of aromatic nitro compounds Aromatic nitro compounds are typically synthesized by nitration. Nitration is achieved using a mixture of nitric acid and sulfuric acid, which produce the nitronium ion (), which is the electrophile: + The nitration product produced on the l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidizer
An oxidizing agent (also known as an oxidant, oxidizer, electron recipient, or electron acceptor) is a substance in a redox chemical reaction that gains or " accepts"/"receives" an electron from a (called the , , or ). In other words, an oxidizer is any substance that oxidizes another substance. The oxidation state, which describes the degree of loss of electrons, of the oxidizer decreases while that of the reductant increases; this is expressed by saying that oxidizers "undergo reduction" and "are reduced" while reducers "undergo oxidation" and "are oxidized". Common oxidizing agents are oxygen, hydrogen peroxide and the halogens. In one sense, an oxidizing agent is a chemical species that undergoes a chemical reaction in which it gains one or more electrons. In that sense, it is one component in an oxidation–reduction (redox) reaction. In the second sense, an oxidizing agent is a chemical species that transfers electronegative atoms, usually oxygen, to a substrate. Combust ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acetylene
Acetylene (systematic name: ethyne) is the chemical compound with the formula and structure . It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is unstable in its pure form and thus is usually handled as a solution. Pure acetylene is odorless, but commercial grades usually have a marked odor due to impurities such as divinyl sulfide and phosphine.Compressed Gas Association (1995Material Safety and Data Sheet – Acetylene As an alkyne, acetylene is unsaturated because its two carbon atoms are bonded together in a triple bond. The carbon–carbon triple bond places all four atoms in the same straight line, with CCH bond angles of 180°. Discovery Acetylene was discovered in 1836 by Edmund Davy, who identified it as a "new carburet of hydrogen". It was an accidental discovery while attempting to isolate potassium metal. By heating potassium carbonate with carbon at very high temperatures, he produced a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitric Acid
Nitric acid is the inorganic compound with the formula . It is a highly corrosive mineral acid. The compound is colorless, but older samples tend to be yellow cast due to decomposition into oxides of nitrogen. Most commercially available nitric acid has a concentration of 68% in water. When the solution contains more than 86% , it is referred to as ''fuming nitric acid''. Depending on the amount of nitrogen dioxide present, fuming nitric acid is further characterized as red fuming nitric acid at concentrations above 86%, or white fuming nitric acid at concentrations above 95%. Nitric acid is the primary reagent used for nitration – the addition of a nitro group, typically to an organic molecule. While some resulting nitro compounds are shock- and thermally-sensitive explosives, a few are stable enough to be used in munitions and demolition, while others are still more stable and used as pigments in inks and dyes. Nitric acid is also commonly used as a strong oxidizing agen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acid Dissociation Constant
In chemistry, an acid dissociation constant (also known as acidity constant, or acid-ionization constant; denoted ) is a quantitative measure of the strength of an acid in solution. It is the equilibrium constant for a chemical reaction :HA A^- + H^+ known as dissociation in the context of acid–base reactions. The chemical species HA is an acid that dissociates into , the conjugate base of the acid and a hydrogen ion, . The system is said to be in equilibrium when the concentrations of its components will not change over time, because both forward and backward reactions are occurring at the same rate. The dissociation constant is defined by :K_\text = \mathrm, or :\mathrmK_\ce = - \log_ K_\text = \log_\frac where quantities in square brackets represent the concentrations of the species at equilibrium. Theoretical background The acid dissociation constant for an acid is a direct consequence of the underlying thermodynamics of the dissociation reaction; the p''K''a v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hückel Rule
Hückel or Huckel may refer to: * Erich Hückel (1896-1980), German physicist and chemist ** Debye–Hückel equation (named after Peter Debye and Erich Hückel), in chemistry, a method of calculating activity coefficients ** Hückel method (named after Erich Hückel), a method for the determination of energies of molecular orbitals *** Extended Hückel method, considers also sigma orbitals (whereas the original Hückel method only considers pi orbitals) ** Hückel's rule (named after Erich Hückel), a method of determining aromaticity in organic molecules * (1895-1973), German chemist * (born 1936), German diplomat, Ambassador of the GDR in Chad {{disambig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
