Further Studies on the Dissociation of HBr Behind Shock Waves

Previously reported shock tube studies of the dissociation of HBr in the temperature range of 2100-4200K have been extended to lower temperatures 1450-2300K in pure HBr. The results imply that, in the lower range of temperatures, the activation energy of dissociation can be approximated by the HBr bond energy 88 kcalmole. It was also found that, in this temperature range, the rate of HBr dissociation is sensitive to the Br 2 dissociation rate and the HBr Br exchange rate. It was found that the higher temperature data could also be fitted reasonably well with an HBr dissociation activation energy of 88 kcalmole, contrary to the conclusions of previous work. A detailed review is given of the rate coefficients for the other pertinent reactions in the H2- Br2 system namely, Br2 dissociation and reactions of HBr with H and Br.