Experimental Observation and Modeling of Potential Oscillations on Iron Electrodes

A comprehensive laboratory exercise is described whereby students measure oscillations in electric potential between iron and carbon electrodes immersed in an acidic solution of hydrogen peroxide. The oscillations observed vary greatly in complexity. After collecting the data, students use a kinetic mechanism to qualitatively model some of the less complex oscillations. The experiment is straightforward to carry out and uses materials commonly found in chemistry laboratories. In addition, the proposed mechanism involves a variety of iron species that are familiar to students of chemistry.