Using yeast, sugar, and water, learners create a chemical reaction which produces carbon dioxide (CO2) gas inside a 2-liter bottle. They use this gas to inflate a balloon. This reaction shows the process of fermentation, a common reaction to make bread, beer, or wine. This activity, located on page 2 of the PDF, is a take-home version of the display of the same name in the Biochemistry unit of OMSI's Chemistry Lab. Included in the PDF are two additional activities: Egg Osmosis and Cabbage Juice Indicator.