Hydrogen peroxide yields in the hydrogen + oxygen reaction. Reaction of HO2 radicals with hydrogen

Abstract

An improved sampling method has yielded reproducible results for the concentrations of H₂O₂ present in slowly reacting H₂+ O₂ mixtures at 500°C. The observed yields have been compared with those predicted by computer programmes with a mechanism containing the two alternative reactions (11) and (11a) for the reaction of HO₂ radicals with H₂. HO₂+ H₂= H₂O₂+ H (11) HO₂+ H₂= H₂O + OH (11a) The values of k₁₁ and k_11a are obtained from an interpretation of the induction periods preceding slow reaction.

The comparison indicates that for the H₂+ O₂ reaction, (11a) plays a negligible part in the mechanism. However, since the value for k_11a required to interpret the induction periods is almost 10 times the value required for k₁₁, it is not possible to exclude entirely the possibility that, from the point of view of HO₂ radicals, reactions (11) and (11a) are of equal importance.