The thermal decomposition of nitromethane has been studied by a static Eethod over the range 380-430° C, and shown t o be a homogeneous reaction, of approximately first order at pressures between 200 and 400 mm., with a rate constant given by k = 1014-6 exp (-53,60o/RT) sec.-l.The main produch are nitric oxide, methane, carbon monoxide and water, with some carbon dioxide, and small quantities of ethane, ethylene and nitrous oxide. The initial step is considered t o be CH,N02 + CH, + NO2, followed by a non-chain radical mechanism. C-N bond in nitromethane is thus estimated t o be 53 kcal.

The thermal decomposition of nitroethane has been studied by a static method over the temperature range 355-405' C, and shown to be a largely homogeneous reaction of the first order in the pressure range 50-300 mm. Under the conditions used, the extent of heterogeneous reaction was estimated to be about 10 yo, with the consequence that the estimated equation for the rate constant of the homogeneous reaction, k = 1 0 ~3 ' ~ e-47,000/aT sec.-l, is subject to an uncertainty which is not easy to estimate. The activation energy is, however, unlikely to be in error by more than 2 kcal. The main gaseous products are ethylene and nitric oxide, with some oxides of carbon. I-Nitropropane, which was studied in less detail, has an activation energy of about 5 0 kcal., and the products include propylene. The mechanism is considered to be a unimolecular reaction to give the olefin and HNO,, followed by oxidation of some of the olefin.