REACTION OF METHOXY RADICALS WITH NITRIC-OXIDE AND NITROGEN-DIOXIDE

By allowing dimethyl peroxide (10−4M) to decompose in the presence of nitric oxide (4.5 × 10−5M), nitrogen dioxide (6.5 × 10−5M) and carbon tetrafluoride (500 Torr), it has been shown that the ratio k2/k2′ = 2.03 ± 0.47: CH3O + NO → CH3ONO (reaction 2) and CH3O + NO2 → CH3ONO2 (reaction 2′). Deviations from this value in this and previous work is ascribed to the pressure dependence of both these reactions and heterogeneity in reaction (2). In contrast no heterogeneous effects were found for reaction (2′) making it an ideal reference reaction for studying other reactions of the methoxy radical. We conclude that the ratio k2/k2′ is independent of temperature and from k1 = 1010.2±0.4M−1 sec−1 we calculate that k2′ = 109.9±0.4M−1 sec−1. Both k2 and k2′ are pressure dependent but have reached their limiting high‐pressure values in the presence of 500 Torr of carbon tetrafluoride. Preliminary results show that k4 = 10.9.0±0.6 10−4.5±1.1/ΘM−1 sec−1 (Θ = 2.303RT kcal mole−1) and by k4 = 108.6±0.6 10−2.4±1.1/ΘM−1 sec−1: CH3O + O2 → CH2O + HO2 (reaction 4) and CH3O + t‐BuH → CH3OH + (t‐Bu) (reaction 4′). Copyright © 1979 John Wiley & Sons, Inc.