The Reaction of Hydrogen Atoms with the Paraffin Hydrocarbons

Abstract

The reactions of atomic hydrogen produced by a discharge with ethane, propane, and neo‐pentane have been investigated. All three reactions proceed at approximately the same rate, with activation energies of ca. 9 kcal., assuming a steric factor of 0.1. It is suggested, however, that the activation energies are in reality somewhat lower than this, with correspondingly smaller steric factors. In the reaction with neo‐pentane considerable ethane is produced. When deuterium atoms are used, this ethane is found to be only slightly exchanged. It is concluded, therefore, that ethane cannot arise by recombination of radicals, and must be formed in one step, presumably from an excited neo‐pentane molecule.