M.S. / Chemistry / The present investigation concerns itself with the study of the pressure dependence of hydrogen adsorption on a platinum electrode in acid media. The specific intent of this work is to find whether additional hydrogen adsorbs onto a platinum electrode when the system pressure is increased. Through this means it is possible to prove or disprove the assumption usually made that hydrogen forms a monolayer on a platinum electrode at one atmosphere pressure. Secondary aspects of this study are the effects of diffusion of hydrogen atoms into the electrode bulk, and the desorption and diffusion of hydrogen molecules into the solution layer surrounding the electrode.