Dinitrogen concentration increase

Reducing the temperature or increasing the concentration of reactants, particularly of dinitrogen pentoxide, advanced the onset and increased the intensity of the autocatalysis. Added nitric acid and, to a greater extent sulphuric acid, made the effect more prominent. 

Vandoni and Viala examined the vapour pressures of mixtures of nitric acid in acetic anhydride, and concluded that from o to mole-fraction of nitric acid the solution consisted of acetyl nitrate, acetic acid and excess anhydride in equimolar proportions the solution consisted of acetyl nitrate and acetic acid, and on increasing the fraction of nitric acid, dinitrogen pentoxide is formed, with a concentration which increases with the concomitant decrease in the concentration of acetyl nitrate. 

In solutions of acetyl nitrate in acetic anhydride, prepared from purified nitric acid, the 0 -ratio increases slightly with increasing concentrations of acetyl nitrate (table 5.7, expts. 11,13,16). The use of fuming nitric acid in the preparation of the acetyl nitrate considerably accelerates the rates of reaction and also increases the proportion of o-substitution (table 5.7, expts. 12, 15, 18). These effects resemble, but are much stronger than the corresponding effects in nitrations with solutions of nitric acid in acetic acid contaimng dinitrogen tetroxide. 

The effect on decrease in hypergolic ignition delay of increasing concentrations of dinitrogen tetraoxide in red fuming nitric acid was studied with triethylamine, dimethylhydrazine orm/xo-xylidine as fuels [1], The effect of various catalysts on ignition delay after contact of red fuming nitric acid with various arylamine—formaldehyde condensation products was also studied [2,3]. 

With increasing concentration of nitric acid, dinitrogen oxide (N20) nitrogen oxide (NO) are formed ... 

Ammonium seems to be significantly attenuated in the anaerobic part of the plume as indicated by the detailed investigation of the Grindsted Landfill (DK) leachate plume. The ammonium plume is of limited extent. It is followed by zones of increasing concentration of nitrate and dinitrogen oxide, but the attenuation mechanisms of ammonium are not understood. This issue deserves further research, as ammonium may be seen as one of the critical compounds in landfill leachate plumes (Christensen et al., 2000a). 

The stoichiometry is more complicated here because 2 mol of dinitrogen pentoxide produce 4 mol of nitrogen dioxide and 1 mol of oxygen. So, it is no longer true that the rate of decrease of the reactant concentration equals the rates of increase of the product concentrations. However, this difficulty can be overcome if, in order to define the reaction rate, we divide by the coefficients from the balanced equation. For this reaction, we get the following. 

Dinitrogen trioxide reacts with the unshared pair of electrons on unprotonated secondary amine by a nucleophilic substitution reaction to form nitrosamines. The rate of nitrosation of secondary amines in a weakly acidic aqueous solution is proportional to the concentration of the amines and to the square of the nitrite concentration. The concentrations of these two precursors depend on the pH of the medium. While the concentration of unprotonated amines increases when pH increases, the concentration of nitrous acid increases when the pH decreases. Hence, the pH rate profile for the nitrosation of amines shows a maximum resulting from the interaction between these two opposite... 

Ozone is formed by the photolytic decomposition of NO2 yielding oxygen radicals and by the reaction sequence NO2 — HNO3 — NO3 O3. In particular, the reaction of NO2 with hydroxyl radicals to form HNO3 increases ozone concentration because two radicals, NO2- and -OH, which catalyze ozone decomposition, are removed. Other radicals are also important for ozone destruction in the stratosphere, especially chlorine oxides see Chlorine, Bromine, Iodine, Astatine Inorganic Chemistif). The mechanism of ozone destruction is complicated as there many compounds involved. Chlorine nitrate and dinitrogen pentoxide can act as reservoir species for CIO-, NO2-, and NO3- radicals. 

Complexes of vanadium(O) with dinitrogen were obtained by co-condensations. [V(N2)e] has been prepared in frozen matrices this formulation was based on the similarity of IR and UV-vis spectra with the corresponding [V(CO)6]- By increasing the vanadium concentration, changes in the IR were explained as due to a dimer, [V2(N2)i2]- Dinitrogen is acting as a weak ligand compared with CO, i.e. a poorer o donor and a poorer Ji acceptor. ... 

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