Ozone nitric oxide reaction pathway

In order to calculate the steady-state concentration of ozone in the stratosphere, we need to balance the rate of production of odd oxygen with its rate of destruction. Chapman originally thought that the destruction was due to the reaction O + 03 —> 2O2, but we now know that this pathway is a minor sink compared to the catalytic destruction of 03 by the trace species OH, NO, and Cl. The former two of these are natural constituents of the atmosphere, formed primarily in the photodissociation of water or nitric oxide, respectively. The Cl atoms are produced as the result of manmade chlorofluorocarbons, which are photodissociated by sunlight in the stratosphere to produce free chlorine atoms. It was Rowland and Molina who proposed in 1974 that the reactions Cl + 03 —> CIO + O2 followed by CIO + O —> Cl + O2 could act to reduce the concentration of stratospheric ozone.10 The net result of ah of these catalytic reactions is 2O3 — 3O2. 

Although a-dicarbonyl compounds are not known to be products of the ozonolysis of olefins, biacetyl has been isolated in photochemically initiated reactions 14, 15) which result in the net oxidation of olefins in the gas phase. For example, when a mixture of ci5-2-butene, nitric oxide, and air is irradiated, small amounts of biacetyl are isolated. One of the pathways suggested to explain the production of biacetyl involves the reaction of ozone with ci5-2-butene (14) ... 

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