The activity of the vanadium-magnesium oxide catalyst was tested in the reaction of isobutane dehydrogenation reaction in the presence and absence of carbon dioxide. The data were compared with the results obtained in the Boudouard and the reverse water gas shift reactions. It has been found that carbon oxide is produced with both RWGS reactions coupled with the simple dehydrogenation of isobutane (i.e., two-step pathway) and the one-step oxidative dehydrogenation reaction.