Decomposition of BrO studied by kinetic spectroscopy

Abstract

Kinetics of BrO decomposition was studied between 293 and 673 °K using the technique of kinetic spectroscopy. At 293 °K the reaction rate is second order with respect to BrO and is independent of [Br2], [O2], and total pressure of diluent gas. The activation energy for decomposition obtained from rate measurements between 293 and 450 °K is 0.65 ± 0.05 kcal/mole. Above 450 °K this activation energy appears to increase to 4.5 kcal/mole. It is shown that, although kinetically the ClO and BrO decompositions are similar, the mechanism for BrO decomposition below 450 °K is much simpler than that of ClO. The reaction proceeds, most likely, via one step: 2 BrO → 2 Br + O2, with Br2O2 being an activated complex, which has either linear or staggered configuration. ClO and BrO decomposition is compared with [Formula: see text] reaction.