Ozone reaction with nitrogen dioxide

Propylene forms explosive mixtures with air within the range 2.4-10.3% by volume. Violent explosion may occur by mixing propylene with fluorine or nitrogen dioxide. Reactions with ozone or hydrogen peroxide... 

The nitrate radical (NO3) is formed in the atmosphere primarily by the reaction of nitrogen dioxide (NO2) with ozone (O3). At the outset of this project the potential importance of the role of NO3 as an oxidant in the troposphere had just been recognised. In order to assess the latter accurate physico-chemical models, describing the behaviour of NO3 in the troposphere, are needed. These require a detailed understanding of the elementary photochemical or chemical reactions and physical processes such as deposition or transport, which determine the tropospheric lifetime of NO3. 

Radicals of nitrogen trioxide (NO3) have a significant role in the chemical processes occnrring in the top layers of the atmosphere [1]. They are produced in the gas phase by the reaction of nitrogen dioxide (NO ) with ozone ... 

Much evidence has been accumulated that the ozone-olefin reaction has a predominant role in aerosol formation from alkenes, cyclic olefins, diolefins, and other unsaturated compounds. Free radicals are formed in the reaction and can react further, along with nitric oxide and nitrogen dioxide, either with the various intermediates or with the olefin itself (see the recent review by Pitts and Finlayson ). 

Possible atmospheric reaction products are oxy-, hydroxy-, nitro- and hydroxynitro-PAH derivatives (Baek et al. 1991). Photochemical oxidation of a number of PAHs has been reported with the formation of nitrated PAHs, quinones, phenols, and dihydrodiols (Holloway et al. 1987 Kamens et al. 1986). Some of these breakdown products are mutagenic (Gibson et al. 1978). Reaction with ozone or peroxyacetyinitrate yields diones nitrogen oxide reactions yield nitro and dinitro PAHs. Sulfonic acids have also been formed from reaction with sulfur dioxide. 

In the stratosphere nitric oxide is converted to nitrogen dioxide by reaction with ozone ... 

Nitric oxide is quite rapidly oxidized to N02 by reaction with ozone. Nitrogen dioxide, in turn, is subject to photolysis whereby NO is regenerated. This leads to the following reaction sequence... 

Nitric oxide gives a chemiluminescence emission when reacted with ozone to yield electronically excited nitrogen dioxide (reaction [I]) ... 

Indigo-5,5 -disulfonate (or trisulfonate) reacts with ozone as described in the CL section. The blue color of IDS disappears on reaction with ozone and the decrease in absorbance at 610 mn is measured. As the molar absorptivity ( 2x 10" moll cm ) depends on the brand and batch of commercially available IDS probably due to impurity, the apparent reaction stoichiometry of IDS to ozone is not exactly unity. However, the stoichiometric ratio is reproducible when the same IDS reagent is used throughout. Nitrogen dioxide interferes positively by 6% of the mass of NO2, but SO2, NO, HF, H2S, H2O2, and peroxyacetyl nitrate do not interfere. Sampling time... 

The reaction of HS with oxygen is slow, whereas reactions with ozone and nitrogen dioxide are rapid. Both produce the HSO radical, for example... 

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

Here a chemical reaction produces a molecule with electrons in an excited state. Upon decay to the ground state the liberated radiation is detected. One such example is the reaction between ozone and nitric oxide to form nitrogen dioxide emitting radiation in the near infra-red in the 0.5-3/t region. The technique flnds use for measuring nitric oxide in ambient air or stack emissions. 

Reaction of benzanthrone with nitrogen dioxide alone or in admixture with ozone gives a mixture of nitrated products including 3-nitrobenzanthrone, which is a new class of powerful direct-acting mutagens of atmospheric origin (Eq. 2.12).26... 

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