Oxidation-reduction reactions internal

Exothermic oxidation—reduction reactions provide the energy released in both propellant burning and explosive detonation. The reactions are either internal oxidation—reductions, as in the decomposition of nitroglycerin and pentaerythritol tetranitrate, or reactions between discrete oxidizers and fuels in heterogeneous mixtures. 

RocketPropella.nts, Liquid propellants have long been used to obtain maximum controUabiUty of rocket performance and, where required, maximum impulse. Three classes of rocket monopropellants exist that differ ia the chemical reactions that release energy (/) those consisting of, eg, hydrogen peroxide, ethylene oxide, C2H4O and nitroethane, CH2CH2NO2 that can undergo internal oxidation—reduction reactions (2) those... 

NH2OH can exist as 2 configurational isomers (cis and trans) and in numerous intermediate gauche conformations as shown in Fig. 11.7. In the crystalline form, H bonding appears to favour packing in the trans conformation. The N-O distance is 147 pm consistent with its formulation as a single bond. Above room temperature the compound decomposes (sometimes explosively) by internal oxidation-reduction reactions into a complex mixture of N2, NH3, N2O and H2O. Aqueous solutions are much more stable, particularly acid solutions in which the compound... 

Some internal oxidation-reduction reactions have been reported with the bisulfite adducts of naphtho[l,2-c]furoxan " and some... 

The base was being prepared by distilling a mixture of hydroxylamine hydrochloride and sodium hydroxide in methanol under reduced pressure, and a violent explosion occurred towards the end of distillation [1], probably owing to an increase in pressure above 53 mbar. It explodes when heated under atmospheric pressure [2], Traces of hydroxylamine remaining after reaction with acetonitrile to form acetamide oxime caused an explosion during evaporation of solvent. Traces can be removed by treatment with diacetyl monoxime and ammoniacal nickel sulfate, forming nickel dimethylglyoxime [3], An account of an extremely violent explosion towards the end of vacuum distillation had been published previously [4], Anhydrous hydroxylamine is usually stored at 10°C to prevent internal oxidation-reduction reactions which occur at ambient temperature [5], See other REDOX REACTIONS... 

Cannizzaro reaction An internal oxidation-reduction reaction of aldehydes, carbamide Urea, carcinogenic Cancer causing. 

Mammalian methylene-THF reductase is a FAD-containing flavoprotein that utilizes NADPH for the reduction to 5-methyl-THF.427,428 Matthews429 suggested that the mechanism of this reaction involves an internal oxidation-reduction reaction that generates a 5-methyl-quinonoid dihydro-THF (Eq. 15-45). Methylene-THF reductase of acetogenic bacteria is also a flavoprotein but it contains Fe-S centers as well. The 237-kDa a4P4 oligomer contains two molecules of FAD and four to six of both Fe and S2 ions.430 431... 

How does the anionic alkyl of the original trialkylaluminum or of the dialkylaiuminum chloride, which has sufficient anionic character to undergo anionic hydride exchange or CH3OT reaction, form a catalyst which becomes cationic under certain polymerization conditions No studies of this have been reported. One possibility is an internal oxidation-reduction reaction that converts an anionic alkyltitanium trichloride to a cationic alkyltitanium trichloride (Equation 10). Basic and electrophilic catalyst components would determine the relative contributions of the anionic and cationic forms. This type of equilibrium or resonance structures could also explain the color in transition metal compounds such as methyltitanium trichloride (73). 

The biochemistry of alcoholic fermentation involves a series of internal enzyme-mediated oxidation-reduction reactions m which glucose is degraded via the Embden-Meyerhof-Parnas pathway See also Carbohydrates and Glycolysis. 

The base- and solvent-catalyzed degradations of NC in solns appear to be internal oxidation-reduction reactions involving splitting of the chain... 

The violet complexes Mn(H2P 07)73 and Mn(C204)73 (both presumably chelates) are also known. The latter, when heated or illuminated strongly, undergoes an internal oxidation-reduction reaction, yielding C02 and an oxalate complex (or complexes) of Mn(II). The stability of the Mn(C204)73 complex at room temperature makes it necessary to carry out the familiar titration of oxalate with permanganate at elevated temperature (>60° 0). 

Introducing excessive amounts of standards into the samples, which disturbs the equilibria in the material as a result of physicochemical modification of the nature of the matrix Introducing an internal standard that interacts with the investigated compounds (via complexing, formation of ion pairs, oxidation-reduction reaction, addition or hydrolysis reactions) Conducting extraction in uncontrolled pH conditions, or under elevated pressure and temperature, triggering processes of hydrolysis or alkylation... 

A similar rearrangement occurs when a-epoxyketones are refluxed with 30% aqueous sodium hydroxide. Best directions ate those for benzilic acid (90%) from benzoin, sodium bromate, and sodium hydroxide. Oxidation of the benzoin to benzil and rearrangement of benzil to benzilic acid are accomplished in one step. a-Ketoaldehydes and potential a-ketoalde-hydes undergo a similar internal oxidation-reduction reaction in excellent yields, viz.,... 

PHRQPITZ retains the original logic of PHREEQE concerning oxidation-reduction reactions, but because an internally-consistent data base of Pitzer interaction parameters for multiple oxidation states is not currently available, geochemical redox reactions may not be attempted in PHRQPITZ. All redox equilibria used with PHREEQE have been removed from the PHRQPITZ data base. Because of the lack of Pitzer interaction parameters for aqueous aluminum and silica species, calculations with aluminosilicates are not possible in PHRQPITZ. 

An example of a reaction in which the reduced form of the metal ion is converted back to its higher oxidation state by molecular oxygen, is the autoxidation of ascorbic acid by copper(II) (206, 207). The probable course of the reaction is as follows The ascorbate ion forms an intermediate copper(II) chelate which undergoes an internal oxidation-reduction reaction, thereby forming a copper(I) semiquinone chelate. Dissociation of the relatively unstable copper(I) chelate occurs and the copper(I) ion is oxidized by molecular oxygen and the semiquinone is oxidized by molecular oxygen or copper(II) (160). 

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