Kinetic study of the reactions of CL and BR with H₂O₂

The reactions of Cl and Br atoms with H 2 O 2 have been studied in the range of 300–350 K using the very‐low‐pressure‐reactor technique. It was found that metathesis to produce HX and HO 2 is the only significant process (≤99%). For the reaction of Br k 2 (300 K) = 1.3 ± 0.45 × 10 −14 and k 2 (350 K) = 3.75 ± 1.1 × 10 −14 cm 3 /molecules·s, with an activation energy of 4.6 ± 0.7 kcal/mol. Using an estimated A factor for A 2 , we find suggesting that a best choice is E 2 = 3.9 ± 0.4 kcal/mol. The relation of these values to Δ H (HO 2 ) is discussed.