Summary: The reactions of recoil carbon with ethylene, ethylene oxide, and isobutane are compared in the gaseous and condensed states. Remarkably little phase dependence of the products of these reactions is found. The results show that there is little if any contribution from mechanisms involving reactions of the carbon atom with radical debris produced in its recoil track. Instead the reactions by which recoil carbon enters combination seem quite analogous to those of similar reactive species (such as CH2) produced by more conventional means. The detailed reaction mechanisms previously proposed for reactions of atomic carbon with gaseous hydrocarbons, C-Η and C=C bond insertions, also appear dominant in the condensed phases. The small changes with phase that are observed are consistent with the expected action of a solvent cage in promoting the de-excitation or secondary reaction of unstable intermediates produced by the insertion reactions