Lightning in a Bottle

Students in general chemistry laboratory investigate the formation of nitrogen oxides (NOx) gases produced by electrical discharge under different experimental conditions. In the first week of this three-week laboratory experiment, students generate NOx gases using the electrical discharge of a Tesla coil to break down N2 and O2 in air. After mixing the reacted sample of gas with an aqueous indicator solution, they quantify the concentration of NOx using spectrophotometric techniques. They select a research question related to the experiment to investigate during the next two laboratory sessions and develop a hypothesis. Based on skills learned during the first week, students design their own experimental procedure, interpret their data, and report an appropriate conclusion. This inquiry experiment introduces students to traditional chemistry topics (e.g., gas laws, dilutions and oxidation-reduction reactions) as well as applications of chemistry such as lightning and atmospheric science.