Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Rate constant for the reaction of H with H/sub 2/O and OH with H/sub 2/ by the flash photolysis-shock tube technique over the temperature range 1246-2297 K

Journal Article · · J. Phys. Chem.; (United States)
DOI:https://doi.org/10.1021/j100324a035· OSTI ID:6480113

Rate constants for the reaction of atomic hydrogen with water, reaction 1, were measured by the flash photolysis-shock tube technique utilizing atomic resonance absorption to monitor the change in H atom concentrations with time. Experiments were carried out over the temperature range 1246-2297 K, and the results can be expressed by the Arrhenius equation k/sub 1/(T) = (4.58 +/- 0.61) x 10/sup -10/ exp((-22966 +/- 482 cal mol/sup -1/)/RT) cm/sup 3/ molecule/sup -1/ s/sup -1/. The errors are given at the one standard deviation level. By use of the known values of the equilibrium constant, K/sub 1/(T), for reaction 1, each experimental k/sub 1/(T) measurement was converted to its corresponding value of the rate constant of the reverse reaction, k/sub -1/(T). Over the temperature range 1246-2297 K, the k/sub -1/(T) results can be expressed by the Arrhenius equation k/sub -1/(T) = (1.05 +/- 0.17) x 10/sup -10/ exp((-8037 +/- 482 cal mol/sup -1/)/RT) cm/sup 3/ molecule/sup -1/ s/sup -1/. A composite data base for k/sub -1/(T) was constructed for the temperature range 250-2581 K from the present results and selected previously published data. The resulting Arrhenius plot is nonlinear and may be fitted by the three-parameter expression k/sub -1/(T) = 3.59 x 10/sup -16/T/sup 1.51/ exp(-1726 K/T) cm/sup 3/ molecule/sup -1/ s/sup -1/. These results are compared to earlier experimental measurements and to recently reported theoretical calculations.

Research Organization:
Brookhaven National Lab., Upton, NY (USA)
DOE Contract Number:
AC02-76CH00016
OSTI ID:
6480113
Journal Information:
J. Phys. Chem.; (United States), Journal Name: J. Phys. Chem.; (United States) Vol. 92:13; ISSN JPCHA
Country of Publication:
United States
Language:
English