FTIR study of the reaction of ethyl radicals with O₂ and Cl₂ in air at 295 K

Using Fourier transform infrared spectroscopy, the ethene yield from the reaction of C₂H₅ radicals with O₂ has been determined to be 1.50 ± 0.09%, 0.85 ± 0.11%, and <0.1% at total pressures of 25, 50, and 700 torr, respectively. Additionally, the rate constant of the reaction of C₂H₅ radicals with molecular chlorine was measured relative to that with molecular oxygen. (Formula Presented.) A ratio k₆/k₇ = 1.99 ± 0.14 was measured at 700 torr total pressure which, together with the literature value of k₇ = 4.4 × 10⁻¹² cm³ molecule⁻¹s⁻¹, yields k₆ = (8.8 ± 0.6) × 10⁻¹² cm³ molecule⁻¹s⁻¹. Quoted errors represent 2σ. These results are discussed with respect to previous kinetic and mechanistic studies of C₂H₅ radicals.