There is a need for an updated physical chemistry laboratory curriculum that explores modern research topics and concerns that are important to students, particularly relating to environmental processes. With increased efforts towards green chemistry practices and environmental awareness, contemporary students are concerned with the role of chemistry in the production of harmful compounds and their impact on the planet. This laboratory experiment models how rising atmospheric carbon dioxide concentrations due to the burning of fossil fuels affect the world’s oceans. CO2 is chemically unreactive in the atmosphere, though it becomes reactive once dissolved in water. Aqueous CO2 can react to form carbonic acid, which will dissociate into HCO3− and CO32−, causing a decrease in pH. An increase in ocean acidity decreases the necessary supply of carbonate available to biological systems and can be detrimental to aquatic life. Using a pH probe and pressure sensor, an experimental pressure chamber can be constructed to model equilibrium thermodynamics and Henry’s Law. Students are able to visualize the pH and pCO2 relationship, quantify all pH-dependent species using non-linear algebra, and discuss complex equilibria and trends in relation to ocean acidification.

CO2 equilibrium experiment for climate change-themed physical chemistry laboratory

ACS Spring Meeting 2021

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.