Photodecomposition is part of many vital chemical and biological processes, including, but not limited to, the degradation of ozone, DNA, and even sunblock. We have designed an experiment to study photodecomposition reactions that occur on minute-to-hour timescales. Using modular components, our custom-built instrumentation tracks photodecomposition by monitoring how the color of a chemical changes over time when subjected to irradiation with ultraviolet and/or visible light. Our experiment has been used to study the decomposition of the molecule tetrachoroaurate in the presence of various alcohols. Initial results indicate that the presence of alcohol increases the rate of photodecomposition, but it is still unclear why. Additionally, we have observed that the photodecomposition of tetrachloroaurate can exhibit oscillatory behavior under certain conditions, which is a rare and exciting find in the field of chemistry.
