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Hyponitrous Acid
Hyponitrous acid is a chemical compound with formula or HON=NOH. It is an isomer of nitramide, H2N−NO2; and a formal dimer of azanone, HNO. Hyponitrous acid forms two series of salts, the hyponitrites containing the N=NOsup>2− anion, and the "acid hyponitrites" containing the ON=NOsup>− anion. Structure and properties There are two possible structures of hyponitrous acid, ''trans'' and ''cis''. ''trans''-Hyponitrous acid forms white crystals that are explosive when dry. In aqueous solution, it is a weak acid (p''K''a1 = 7.21, p''K''a2 = 11.54), and decomposes to nitrous oxide and water with a half life of 16 days at 25 °C at pH 1–3: : → + Since this reaction is not reversible, should not be considered as the anhydride of . The ''cis'' acid is not known, but its sodium salt can be obtained. Preparation Hyponitrous acid (''trans'') can be prepared from silver(I) hyponitrite and anhydrous HCl in ether: : + 2 HCl → + 2 AgCl Spectroscopic data indicat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyponitrite
In chemistry, hyponitrite may refer to the anion ( N=NOsup>2−), or to any ionic compound that contains it. In organic chemistry, it may also refer to the group −O−N=N−O−, or any organic compound with the generic formula R1−O−N=N−O−R2, where R1 and R2 are organic groups.M. N. Hughes (1968), "Hyponitrites". Quarterly Reviews of the Chemical Society, volume 22, issue 1, pages 1–13. . Such compounds can be viewed as salts and esters of respectively hyponitrous acid or HON=NOH. An acid hyponitrite is an ionic compound with the anion ( ON=NOsup>−). Hyponitrite ion Hyponitrite exhibits cis–trans isomerism.Egon Wiberg, Arnold Frederick Holleman (2001) ''Inorganic Chemistry'', Elsevier The ''trans'' (''E'') form is generally found in hyponitrite salts such as sodium hyponitrite () and silver(I) hyponitrite (). The ''cis'' (''Z'') form of sodium hyponitrite can be obtained too, and it is more reactive than the ''trans'' form. The ''cis'' hyponitrite anion ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxylamine
Hydroxylamine is an inorganic compound with the formula . The material is a white crystalline, hygroscopic compound.Greenwood and Earnshaw. ''Chemistry of the Elements.'' 2nd Edition. Reed Educational and Professional Publishing Ltd. pp. 431–432. 1997. Hydroxylamine is almost always provided and used as an aqueous solution. It is consumed almost exclusively to produce Nylon-6. It is also an intermediate in biological nitrification. The oxidation of to hydroxylamine is a step in biological nitrification. History Hydroxylamine was first prepared as hydroxylammonium chloride in 1865 by the German chemist Wilhelm Clemens Lossen (1838-1906); he reacted tin and hydrochloric acid in the presence of ethyl nitrate. It was first prepared in pure form in 1891 by the Dutch chemist Lobry de Bruyn and by the French chemist Léon Maurice Crismer (1858-1944). The coordination complex , known as Crismer's salt, releases hydroxylamine upon heating. Production Hydroxylamine or its salts can be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chemical Reaction
A chemical reaction is a process that leads to the IUPAC nomenclature for organic transformations, chemical transformation of one set of chemical substances to another. Classically, chemical reactions encompass changes that only involve the positions of electrons in the forming and breaking of chemical bonds between atoms, with no change to the Atomic nucleus, nuclei (no change to the elements present), and can often be described by a chemical equation. Nuclear chemistry is a sub-discipline of chemistry that involves the chemical reactions of unstable and radioactive Chemical element, elements where both electronic and nuclear changes can occur. The substance (or substances) initially involved in a chemical reaction are called reagent, reactants or reagents. Chemical reactions are usually characterized by a chemical change, and they yield one or more Product (chemistry), products, which usually have properties different from the reactants. Reactions often consist of a sequence o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catalysis
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst. Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyponitrite Reductase
In enzymology, a hyponitrite reductase is an enzyme that catalysis, catalyzes the oxidation of hydroxylamine by the nicotinamide adenine dinucleotide cation (NAD+) into hyponitrous acid HON=NOH: :2 + 2 NAD+ \rightleftharpoons HON=NOH + 2 NADH + 2 H+ This list of enzymes, systematic name of this enzyme class hydroxylamine:NAD+ oxidoreductase. It is also called NADH2:hyponitrite oxidoreductase. This enzyme belongs to the family of oxidoreductases, specifically those acting on other nitrogenous compounds as donors with NAD+ or NADP+ as acceptor. It employs one cofactor (biochemistry), cofactor, metal. References * EC 1.7.1 NADH-dependent enzymes Metal enzymes Enzymes of unknown structure {{1.7-enzyme-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enzymology
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. Almost all metabolic processes in the cell need enzyme catalysis in order to occur at rates fast enough to sustain life. Metabolic pathways depend upon enzymes to catalyze individual steps. The study of enzymes is called ''enzymology'' and the field of pseudoenzyme analysis recognizes that during evolution, some enzymes have lost the ability to carry out biological catalysis, which is often reflected in their amino acid sequences and unusual 'pseudocatalytic' properties. Enzymes are known to catalyze more than 5,000 biochemical reaction types. Other biocatalysts are catalytic RNA molecules, called ribozymes. Enzymes' specificity comes from their unique three-dimensional structures. Like all catalysts, enzymes increase the reaction ra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrous Acid
Nitrous acid (molecular formula ) is a weak and monoprotic acid known only in Solution (chemistry), solution, in the gas phase and in the form of nitrite () salts. Nitrous acid is used to make diazonium salts from amines. The resulting diazonium salts are reagents in azo coupling reactions to give azo dyes. Structure In the gas phase, the planar nitrous acid molecule can adopt both a ''syn'' and an ''anti'' form. The ''anti'' form predominates at room temperature, and infrared spectroscopy, IR measurements indicate it is Gibbs free energy, more stable by around 2.3 kJ/mol. p. 462. Image:Trans-nitrous-acid-2D-dimensions.png , Dimensions of the ''anti'' form(from the rotational spectroscopy, microwave spectrum) Image:Trans-nitrous-acid-3D-balls.png , ball-and-stick model, Model of the ''anti'' form Image:Cis-nitrous-acid-3D-balls.png , ''syn'' form Preparation Nitrous acid is usually generated by acidification of aqueous solutions of sodium nitrite with a mineral acid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diethyl Ether
Diethyl ether, or simply ether, is an organic compound in the ether class with the formula , sometimes abbreviated as (see Pseudoelement symbols). It is a colourless, highly volatile, sweet-smelling ("ethereal odour"), extremely flammable liquid. It is commonly used as a solvent in laboratories and as a starting fluid for some engines. It was formerly used as a general anesthetic, until non-flammable drugs were developed, such as halothane. It has been used as a recreational drug to cause intoxication. Production Most diethyl ether is produced as a byproduct of the vapor-phase hydration of ethylene to make ethanol. This process uses solid-supported phosphoric acid catalysts and can be adjusted to make more ether if the need arises. Vapor-phase dehydration of ethanol over some alumina catalysts can give diethyl ether yields of up to 95%. Diethyl ether can be prepared both in laboratories and on an industrial scale by the acid ether synthesis. Ethanol is mixed with a stro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitramide
Nitramide is a chemical compound with the molecular formula H2NNO2. Organyl derivatives of nitramide, RNHNO2 are termed nitroamines, and are widely used as explosives: examples include RDX and HMX. It is an isomer of hyponitrous acid. Structure The nitramide molecule is essentially an amine group (-NH2) bonded to a nitro group (-NO2). It is reported to be non-planar in the gas phase, but planar in the crystal phase. Synthesis Thiele and Lachman's original synthesis of nitramide involved the hydrolysis of potassium nitrocarbamate: :K2(O2NNCO2) + 2H2SO4 → O2NNH2 + CO2 + 2KHSO4 Other routes to nitramide include hydrolysis of nitrocarbamic acid, :O2NNHCO2H → O2NNH2 + CO2 reaction of sodium sulfamate with nitric acid, :Na(SO3NH2) + HNO3 → O2NNH2 + NaHSO4 and reaction of dinitrogen pentoxide with two equivalents of ammonia. :N2O5 + 2NH3 → O2NNH2 + NH4NO3 Organic nitramides Also called nitramines, organic nitramides are important explosives. They are prepared by nitr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrogen Chloride
The compound hydrogen chloride has the chemical formula and as such is a hydrogen halide. At room temperature, it is a colourless gas, which forms white fumes of hydrochloric acid upon contact with atmospheric water vapor. Hydrogen chloride gas and hydrochloric acid are important in technology and industry. Hydrochloric acid, the aqueous solution of hydrogen chloride, is also commonly given the formula HCl. Reactions Hydrogen chloride is a diatomic molecule, consisting of a hydrogen atom H and a chlorine atom Cl connected by a polar covalent bond. The chlorine atom is much more electronegative than the hydrogen atom, which makes this bond polar. Consequently, the molecule has a large dipole moment with a negative partial charge (δ−) at the chlorine atom and a positive partial charge (δ+) at the hydrogen atom. In part because of its high polarity, HCl is very soluble in water (and in other polar solvents). Upon contact, and HCl combine to form hydronium cations and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver(I) Hyponitrite
Silver hyponitrite is an ionic compound with formula Ag2N2O2 or ()2 N=NOsup>2−, containing monovalent silver cations and hyponitrite anions. It is a bright canary yellow solid practically insoluble in water and most organic solvents, including DMF and DMSO.Trambaklal Mohanlal Oza, Rajnikant Hariprasad Thaker (1955), "The Thermal Decomposition of Silver Hyponitrite". Journal of the American Chemical society, volume 77, issue 19, pages 4976–4980. G. David Mendenhall (1974), "Convenient synthesis of silver hyponitrite". Journal of the American Chemical society, volume 96, issue 15, page 5000. Preparation The compound was described in 1848.(1848), "On the formation of hyponitrite of silver". Philosophical Magazine Series 3, XIII. Intelligence and miscellaneous articles, volume 33 (1848), issue 219, page 75. The salt can be precipitated from a solution of sodium hyponitrite in water by the addition of silver nitrate: : + 2 → + 2 Excess silver nitrate yields a brown or bla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
