Nitrogen oxides and oxyacids

Seven oxides of nitrogen, N20, NO, N203, N204, N02, N205 and N03 have been characterized in all. Of these, N03 cannot be isolated as such, although there is well-documented evidence, both spectroscopic and kinetic, for its existence as a transient species in certain reactions. N203 and N204 possess very weak N-N bonds and exist free of their dissociation products in the condensed phases only. In the gas phase, the equilibria 

Nitric acid is the only oxyacid of nitrogen which is at all stable in the free condition. The kinetics of its decomposition are discussed below. Nitrous acid exists in the gas phase, although it cannot be isolated. Information on the kinetics of its decomposition is restricted to an estimate103 of the half-life of the forward reaction in the rapid gas-phase equilibrium 

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Schwartz SE, White WH. Solubility equilibria of the nitrogen oxides and oxyacids in dilute aqueous solutions. In Pfafflin JR, Zeigler EN, eds. Advances in Environmental Science and Engineering. Vol. 4. New York Gordon and Breach, 1981 1 45. 

S. E. Schwartz, W. H. White, Solubility Equilibria of the Nitrogen Oxides and Oxyacids in Dilute Aqueous Solutions, in Advances in Environmental Science and Engineering, J. R. Pfafflin and E. N. Zeigler (Eds.), Gordon and Breach Science Publ., New York, 1981. 

The discussion that follows first describes techniques for the airborne collection of a definable atmospheric phase for subsequent determinations, then continues with discussion of the analysis techniques themselves including those for nitrogen oxides and oxyacids, sulfur oxides, oxidants and selected organic species. Emphasis is on the modified instrumentation devised and used by Brookhaven National Laboratory staff to improve the selectivity and lower the limits of detection of these techniques (1). 

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