Characteristics of low-temperature combustion

Straight and branched chain reactions almost invariably have complex rate expressions, as shown by -d[H2]/df = A [H2]° [02]° [N2]° for the H2 + O2 reaction in aged boric-acid-coated vessels at 500 Torr and 773 K [6]. Change of pressure can have striking effects even when achieved by addition of an inert gas such as N2. Hydrocarbon combustion reactions proceed through the formation of many intermediates, both radical and molecular, prior to formation of the final products CO2 and H2O. Another striking feature is the sensitivity of chain reactions to traces of impurities and to changes in surface properties. This is particularly pronounced in the case of some explosion boundaries or limits where parts per million quantities of an impurity may completely subdue the explosion. 

In an elementary way, explosion limits may be classified into two types (i) An isothermal limit, where it is the kinetic features of the reaction 

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