RATE CONSTANT FOR THE REACTION NO2 + OH + M-] HNO3 MEASURED UNDER SIMULATED ATMOSPHERIC CONDITIONS USING A NOVEL ANALYSIS PROCEDURE

For the reactions OH + NO2 + M → HNO3 + M (1) and OH + toluene → products (5), we have measured the ratio of rate constants k1/k5 = 2.2 ± 0.2 under simulated atmospheric conditions (T = 301 ± 2 K, P = 780 torr, air, H2O = 11 torr). This measurement was made possible by the development of a novel analysis procedure. Three literature values for the absolute value of k5 agree to within ±5%. Thus we obtain a 1-atm value for k1 of (1.3 ± 0.3) × 10-11 cm-3 s-1. This value, determined under realistic atmospheric conditions in a seemingly complex kinetic system, is in excellent agreement with more direct kinetic measurements. The agreement illustrates the validity of applying basic kinetic data to atmospheric processes and reinforces our understanding of the fate of NO2 in the troposphere. © 1979 American Chemical Society.