Ground-state carbon atoms reactions

Predict the products formed by reaction of ground-state carbon atoms with rw-2-butene and with trans-2-butene. 

FIGURE 11.11 Products formed in the reactions of ground state carbon atoms with unsaturated hydrocarbon molecules under single collision conditions via hydrogen atom elimination. Note that for the reaction of carbon atoms with acetylene, the tricarbon plus molecular hydrogen elimination channel was observed, too. 

The reaction of benzene with a ground state carbon atom,... 

The ground state C atoms are produced by the photolysis of carbon suboxidc. They can be monitored by optical absorption at 1657 A. Reactions of C(3P) atoms with molecules have been studied by Husain and Kirsch (497,498) and Braun et al. (141). 

The reactions between ground-state oxygen atoms and CO have been the subject of many investigations because of the important role they play in carbon monoxide flames and explosions. Basically, two reactions (or reaction sequences) occur one produces ground-state CO2, the other produces electronically excited CO2 which is responsible for the chemiluminescent radiation that used to be referred to as the carbon monoxide flame bands. 

Carbon monoxide also is formed by the reaction of ground state O atoms with OCS the CO vibrational distribution closely resembles the A + BCD prior distribution,or a 9500 K Boltzmann distribution, and = O il- The reaction channel forming SO + CO has a 5 kcal mole" activation energy, and probably corresponds to the SO + CS channel of the O + CS2 reaction. The similarity of and for the two reactions supports this contention. The CO + SO products were not observed in molecular-beam experiment with Et = 5 kcal mole S which is the magnitude of the activation energy. 

Electronic excitation from atom-transfer reactions appears to be relatively uncommon, with most such reactions producing chemiluminescence from vibrationaHy excited ground states (188—191). Examples include reactions of oxygen atoms with carbon disulfide (190), acetylene (191), or methylene (190), all of which produce emission from vibrationaHy excited carbon monoxide. When such reactions are carried out at very low pressure (13 mPa (lO " torr)), energy transfer is diminished, as with molecular beam experiments, so that the distribution of vibrational and rotational energies in the products can be discerned (189). Laser emission at 5 p.m has been obtained from the reaction of methylene and oxygen initiated by flash photolysis of a mixture of SO2, 2 2 6 (1 )-... 

The reactions of ground state atomic carbon, C(3Pj), with unsaturated hydrocarbons are another important class of reactions characterized by multiple pathways. These reactions, besides being of fundamental interest, are of great relevance in the chemistry of the interstellar medium and also in combustion.12,93-95... 

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