Rate coefficients for the reactions CH3 + Br2 (224–358 K), CH3CO + Br2 (228 and 298 K), and Cl + Br2 (228 and 298 K)

✍ Scribed by V. Khamaganov; J. N. Crowley

• Publisher: John Wiley and Sons
• Year: 2010
• Tongue: English
• Weight: 576 KB
• Volume: 42
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/kin.20505

✦ Synopsis

Abstract

Rate coefficients for the reactions of CH~3~ + Br~2~ (k~2~), CH~3~CO + Br~2~ (k~3~), and Cl + Br~2~ (k~5~) were measured using the laser‐pulsed photolysis method combined with detection of the product Br atoms using resonance fluorescence. For the reactions involving organic radicals, the rate coefficients were observed to increase with decreasing temperature and within the temperature range explored, were adequately described by Arrhenius‐like expressions: k~2~ (224–358 K) = 1.83 × 10^−11^ exp(252/T) and k~3~ (228–298 K) = 2.92 × 10^−11^ exp(361/T) cm^3^ molecule^−1^ s^−1^. The total, temperature‐independent uncertainty for each reaction (including possible systematic errors in Br~2~ concentration measurement) was estimated as ∼7% for k~2~ and 10% for k~3~. Accurate data on k~5~ was obtained at 298 K, with a value of 1.88 × 10^−10^ cm^3^ molecule^−1^ s^−1^ obtained (with an associated error of 6%). A limited data set at 228 K suggests that k~5~ is, within experimental uncertainty, independent of temperature. © 2010 Wiley Periodicals, Inc. Int J Chem Kinet 42: 575–585, 2010