Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published November 1979 | public
Journal Article

Pressure and temperature dependence kinetics study of the NO + BrO → NO_2 + Br reaction. Implications for stratospheric bromine photochemistry


The flash photolysis-ultraviolet absorption technique has been utilized to study the reactivity of nitric oxide with BrO radicals over a wide range of pressure (100-700 torr) and temperature (224-398 K). Pseudo-first-order conditions were used in order to minimize complications caused by secondary kinetic processes. The reaction and its corresponding Arrhenius expression in units of cm^3 molecule^(-1) s^(-1) can be written NO + BrO → NO_2 + Br ΔHº_298 = -17.0 kcal mol^(-1) k_1 = (1.28 ± 0.23) x 10^(-11)exp((181 ± 46)/T) (T = 224-398 K) The results are compared with previous measurements, and atmospheric implications of the reaction are discussed. It is shown that this reaction is important in controlling the ratios [BrO]/[Br] and [BrO]/[HBr] in the stratosphere but that it does not affect the catalytic efficiency of BrO, in ozone destruction.

Additional Information

© 1979 American Chemical Society. Received May 21, 1979. We thank J. Linke for his indispensable glass blowing services, G. Tennant and M. Patapoff for their expert assistance in constructing the experimental apparatus, and J. Pinto for use of the output of our one dimensional photochemical model prior to publication. We benefited greatly from discussions with W. B. DeMore. This paper presents the results of one phase of research carried out at the Jet Propulsion Laboratory, California Institute of Technology, under Contract No. NAS7-100, sponsored by the National Aeronautics and Space Administration. Part of this work was supported by NASA Grant NSG 2229 to the California Institute of Technology.

Additional details

August 22, 2023
October 17, 2023