Methods are described whereby quantitative information can be obtained regarding the kinetic parameters of certain of the elementary reactions involved in combustion, if similar data on other constituent steps are available. Thus, by a complete stationary-state analysis of a theoretical model and comparison of its predictions with the results of over-all kinetic experiments, the validity of the model may be tested. Insertion of the kinetic parameters which can be obtained by direct measurement then enables similar data to be obtained for other elementary reactions which are not readily accessible to direct study. This paper shows, in particular, how such general methods can be applied to the spontaneous ignition of n -heptane + oxygen + inert gas mixtures at temperatures from 440°–650°C. In this temperature region, an “olefin” mechanism describes the ignition limit, predicting closely the experimental variations of the limiting pressure for ignition with reactant and inert gas concentrations, with temperature, and with the size and shape of the reaction vessel. It is thus shown, for example, how a value of the activation energy for the reaction: HO 2 +C 7 H 16 →H 2 O 2 +C 7 H 15 can be obtained using the known value of the activation energy for the decomposition of hydrogen peroxide. The relative efficiencies of oxygen and nitrogen as the “second body” in the homolytic breakdown of hydrogen peroxide have also been estimated and the results are able to account quantitatively for the marked promoting effect of inert gases on the ignition of n -heptane.