This project, supported in the Analytical and Surface Chemistry Program, addresses a broad range of topics in ultra high vacuum surface chemistry carried out in Professor Weinberg's laboratory at the University of California-Santa Barbara. The use of atomic hydrogen and atomic oxygen sources to probe the details of Eley-Rideal reactions at well characterized Group VIII metal surfaces is a major focus of the work. Vibrational spectroscopic characterization of intermediates on these surfaces is enabled by the development of digital processing methods for resolution enhancement in electron loss spectroscopy. Time resolved vibrational spectroscopy is used to quantify the process of adsorption assisted desorption of small molecules on these transition metal surfaces, and molecular beam methods are used to probe the flux dependence of adsorption of oxygen and other small molecules. This work provides the knowledge base necessary for the design and understanding of important catalytic and electronic device processing technologies. The detailed study of the mechanisms of surface reaction chemistry on platinum, iridium, and ruthenium surfaces forms the focus of this work. A combination of experimental method development and examination of model reaction systems provides a clearer understanding of the mechanisms of surface reactions and the intermediates involved. This knowledge proves useful in the design and implementation of catalytic and electronic device manufacturing processes.