TEMPERATURE-DEPENDENCE OF THE GAS-PHASE REACTIONS OF CF3O WITH CH4 AND NO

A temperature-regulated flow tube reactor coupled to a chemical ioniza tion mass spectrometer (CIMS) was used to investigate reactions of CF3 O with CH4 and NO. The reaction rate constant for the CF3O + CH4 react ion was measured in the temperature range 231-385 K and found to be k( 3)(T) = (3.1 +/- 0.5) x 10(-12) exp[(-1470 +/- 250) K/T]cm(3) molecule (-1) s(-1), with k(3)(298 K) = (2.2 +/- 0.4) X 10(-14) cm(3) molecule( -1) s(-1) (where the uncertainties represent our estimated accuracy at the 95% confidence level). The latter is in good agreement with recen tly reported measurements at room temperature. The reaction rate const ant for the CF3O + NO reaction was measured in the temperature range 2 31-393 K and found to be k(4)(T) = (4.1 +/- 0.6) X 10(-11) exp[(60 +/- 100)K/T], with k(4)(298 K) = (5.0 +/- 1.0) x 10(-11) cm(3) molecule(- 1) s(-1). The value at room temperature disagrees with two previously reported values by a factor of about 2.5 but is in good agreement with three recently reported values. The results reported in this study ar e important in establishing the fate of the CF3Ox, radicals produced a s degradation products from hydrofluorocarbons (HFC's) in the atmosphe re.