A discharge flow reactor coupled to laser-induced fluorescence (LIF) a
nd mass spectrometry has been used to study the kinetics of the reacti
ons of CH3O with NO and NO3. The value of the rate constant for the re
action CH3O + NO --> products at 298 K and at 1 Torr of He has been fo
und to be k = (4.8 +/- 0.4) x 10(-12) cm(3) molecule(-1) s(-1), in goo
d agreement with the literature data. From the kinetic analysis of CH3
O by LIF, the reaction CH3O +/- NO3 --> CH3O2 + NO2 (1) has been found
to be followed by the reaction CH3O2 + NO3 --> CH3O + NO2 + O-2 (2).
Modeling calculations gave for the rate constants of these two reactio
ns, at 298 K, k(1) = (1.8 +/- 0.5) x 10(-12) cm(3) molecule(-1) s(-1)
and k(2) = (1.2 +/- 0.6) x 10(-12) cm(3) molecule(-1) s(-1). Compariso
n with recent Literature data is given, and the atmospheric implicatio
n for nighttime chemistry is briefly discussed.