Nitrous oxide rate equations

N-nitro amines, RNHN02, decompose to alcohols and nitrous oxide in strong acid media. Rate constants obtained for R = methyl in sulfuric acid222 224 are illustrated as excess acidity plots in Fig. 12.119 This shows multiple curvature, but analysis according to equation (59) shows that one water molecule is involved in the reaction up to about 80 wt% H2S04, and one bisulfate ion above this point, see Fig. 13. The proposed mechanism is shown in Scheme 2. 19... 

Find the rate equation for the thermal decomposition of nitrous oxide in... 

Experiment shows that the primary reaction in the homogeneous decomposition of nitrous oxide proceeds with stoichiometry N20 => N2 + 0.5 02 and rate equation... 

An example of a change satisfying this equation very closely is to be found in the catalytic decomposition of nitrous oxide on the surface of platinum. This reaction is retarded by the oxygen produced in the change itself, and its rate is expressed by the equation d[ N20]= k[ N20] dt l+6[OJ where [N20] = a - x, [02] = x. 

The system of equations obtained from the stage steady-state conditions can be solved without simplifications (it is reduced to a quadratic equation). However, a simple approximate solution is sufficient, based on the rate of nitrous oxide formation, r(3), being much less than the sum (r(1) + r<2)) of the rates along the routes iV and jV<2). 

Calculated fc(5.39) value is extremely low, therefore, the contribution of stage (5.39) to nitrous oxide formation is negligibly small. As (5.39) 0, nitrous oxide synthesis rate will be determined from the following equation ... 

When the rate equation does not correspond stoichiometrically, the reaction is called a nonelementary reaction. Consider the thermal decomposition of nitrous oxide to nitrogen and oxygen as follows ... 

There are very few cases of reactions of zero total order, and so these equations do not have wide application. Most of the known cases involve heterogeneous reactions occurring on surfaces, such as the decomposition of nitrous oxide gas on hot platinum wire, 2N2O 2N2 + O2, and the de-e.omposition of ammonia gas on a hot platinum wire, 2NH3 N2 + 3H2. The explanation seems to be that the reaction occurs only at the surface of the catalyst, and if the surface becomes saturated at a given gas or liquid concentration, further increase in the concentration in these phases cannot further change the surface concentration and so, beyond this point, the reaction seems to proceed at a rate independent of concentration in the gas phase. 

Nitrous oxide decomposes approximately according to a second-order rate equation. The specific reaction rate in the forward direction,... 

Nitrous oxide has been used extensively in radiation chemical studies, because it interacts rapidly with hydrated electrons, more slowly with hydrogen atoms, and not at all with OH radicals (15,16,17, 18, 22). It seems to follow from the stoichiometry of radiation induced radicals and products formed in neutral water solution (15, 16, 17, 18), and from the reaction rates in various chemical systems (1, 2, 3, 21, 37) that N20" spontaneously gives rise to an OH radical according to the following equation ... 

Like Fe11, UIV reacts rapidly with PuIv.389-391 The rate was found to vary inversely with [H+]2 and the reaction proceeded according to equation (180). A stabilizer is necessary to prevent the oxidation of UIV by nitric or nitrous acid according to equations (181)-(183).392 The oxidation... 

A kinetic method for determination of aromatic amines was proposed, based on measuring the development of azo dyes (134) resulting from coupling a diazonium ion derived from a PAA analyte and the chromophoric substrate 1 -(4-hydroxy-6-methylpyrimidin-2-yl)-3-methylpyrazolin-5-one (133), as shown in equation 22. After a short induction period initial rate kinetics can be measured when the process is quite advanced, absorbance reaches a maximum and starts to recede due to oxidation of the azo dye by excess nitrous acid. Each PAA has to be calibrated for its molar absorption coefficient and reaction rate, for optimal measurement. A tenfold excess of 133 over the analytes ensures a pseudo... 

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