The research, in the general area of Analytical and Surface Chemistry, focuses on the detailed dynamics of heterogeneous reactions. The work promises to provide detailed information about reactions at surfaces that is crucial to a basic understanding of surface reaction processes. This sort of information is important in many applications, such as heterogeneous catalysis, corrosion and wear, and electronic device processing. Oxidation of carbon monoxide by oxygen on platinum, oxidation of carbon monoxide by nitric oxide on platinum, and the reduction of nitrogen dioxide by carbon monoxide on gold and platinum surfaces will be studied. The chosen systems provide a progression of reaction energetics and mechanistic differences. A range of surface science probes will be used, and the reactions will be studied using a molecular beam scattering system. The experiments will be interpreted using trajectory calculation modeling.