Nitric oxide oxygen reactions

Four routes to form peroxynitrite from nitric oxide. The reaction of nitric oxide with superoxide is only one mechanism leading to the formation of peroxynitrite. Supetoxide could also reduce the nitrosyidioxyl radical. If nitric oxide is directly reduced to nitroxyl anion, it will react with molecular oxygen to form peroxynitrite. At acidic pH, nitrite may form nitrous acid and nitrosonium ion, which reacts with hydrogen peroxide to form peroxynitrite. 

The first mechanism implies k19 = k5AK11A 11A the second leads to ki9 = k2iKlm- . Independent evidence suggests the existence of both intermediate species in the nitric oxide-oxygen system, and both mechanisms involve entirely reasonable collision complexes. In both, the equilibrium step is rapid, and the overall kinetics are third order. Theoretical calculations based on the activated complex theory were made by assuming a true termolecular reaction the predicted rates agree well with experiment.161 The experimental rate constants are summarized in Tables 4-3 and 4-4. 

The reaction of alkenes with nitric oxide (NO), a mixture of nitric oxide and oxygen, or dinitrogen trioxide leads to /i-nitroso nitro compounds ( / -nitrosites or pseudo-nitrosites), which can convert to nitroso dimers79. Nitroalkenes are common byproducts in these reactions. The formation of /i-nitroso nitro compounds in the reaction between alkenes and nitric oxide is explained by the presence of nitrogen dioxide and dinitrogen trioxide in the nitric oxide. The reaction may be initiated by the attack of the N02 radical on the alkene to give a /i-nitroalkyl radical which then couples with nitric oxide. 

In the case of alumina (or other simple oxides), the reaction occurs at high temperatures and under low space velocity conditions. The activity was found to be improved by the addition of platinum group metals [13, 14] and of transition metal oxides [15], especially copper [16, 17, 18]. For alumina-supported copper oxide catalysts a maximum effect has been found by the addition of 0.3 wt % Cu and it has been considered that, for higher copper contents, the formation of cupric oxide would give a solid selective for the oxidation of the hydrocarbon by oxygen [16]. In the case of alumina-supported Cu-Cs oxide catalysts the formation of an isocyanate species has been evidenced by exposition to mixtures "nitric oxide/oxygen/propene (or acetylene)" but not with propane [18, 19], In fact the mechanism of the reaction and the nature of the active sites are still unknown. 

A reaction order of V2 is often found when dealing with molecules that dissociate before reacting. For example, the initial rate of nitric oxide formation reaction in air at high temperature is first order to nitrogen and half order to oxygen ... 

An important side reaction in all free-radical nitrations is reaction 10, in which unstable alkyl nitrites are formed (eq. 10). They decompose to form nitric oxide and alkoxy radicals (eq. 11) which form oxygenated compounds and low molecular weight alkyl radicals which can form low molecular weight nitroparaffins by reactions 7 or 9. The oxygenated hydrocarbons often react further to produce even lighter oxygenated products, carbon oxides, and water. 

Conversion of Ammonia. Ammonia [7664 1-7] mixed with air and having an excess of oxygen, is passed over a platinum catalyst to form nitric oxide and water (eq. 10). The AH g = —226 kJ/mol of NH consumed (—54 kcal/mol). Heats of reaction have been derived from heats of... 

Oxidation of Nitric Oxide. Nitric oxide [10102 3-9] reacts slowly with oxygen to yield nitrogen dioxide [10102 4-0] according to the reversible reaction (eq. 12) for which A 7/295 —57kJ/mol of NO consumed (13.6 kcal/mol). 

Hydroxylamine sulfate is produced by direct hydrogen reduction of nitric oxide over platinum catalyst in the presence of sulfuric acid. Only 0.9 kg ammonium sulfate is produced per kilogram of caprolactam, but at the expense of hydrogen consumption (11). A concentrated nitric oxide stream is obtained by catalytic oxidation of ammonia with oxygen. Steam is used as a diluent in order to avoid operating within the explosive limits for the system. The oxidation is followed by condensation of the steam. The net reaction is... 

G. Fisher and co-workers, "Mechanism of the Nitric Oxide—Carbon Monoxide—Oxygen Reaction Over a Single Crystal Rhodium Catalyst," in M. 

The reaction between nitric oxide, NO, and oxygen, 02, is written... 

Nitric oxide, NO, releases 13.5 kcal/mole when it reacts with oxygen to give nitrogen dioxide. Write the equation for this reaction and predict the effect of (i) raising the temperature, and of (ii) increasing the concentration of NO (at a fixed temperature) on ... 

Nitric acid, manufacture, 45, 232 Nitric oxide as catalyst, 227 reaction with oxygen, 26 solubility, 20 Nitrobenzene, 344 Nitrogen... 

H.20 The first stage in the production of nitric acid by the Ostwald process is the reaction of ammonia gas with oxygen gas, producing nitric oxide gas, NO, and liquid water. The nitric oxide further reacts with oxygen to produce nitrogen dioxide gas, which, when dissolved in water, produces nitric acid and nitric oxide. Write the three balanced equations that lead to the production of nitric acid. 

Their rates are decreased or the reactions are suppressed entirely by substances that scavenge free radicals (e.g., nitric oxide, molecular oxygen, or benzo-... 

The nitric oxide produced in this reaction reacts with ozone to regenerate oxygen and nitrogen dioxide ... 

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