FTIR study of the reaction of ethyl radicals with O 2 and Cl 2 in air at 295 K

Using Fourier transform infrared spectroscopy, the ethene yield from the reaction of C 2 H 5 radicals with O 2 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 C 2 H 5 radicals with molecular chlorine was measured relative to that with molecular oxygen.A ratio k 6 / k 7 = 1.99 ± 0.14 was measured at 700 torr total pressure which, together with the literature value of k 7 = 4.4 × 10 −12 cm 3 molecule −1 s −1 , yields k 6 = (8.8 ± 0.6) × 10 −12 cm 3 molecule −1 s −1 . Quoted errors represent 2σ. These results are discussed with respect to previous kinetic and mechanistic studies of C 2 H 5 radicals.