This document summarizes an experiment demonstrating Gay-Lussac's Law using balloons. The experiment involves heating air in a bottle with a balloon attached, causing the balloon to expand as the air temperature and volume increase proportionally according to Gay-Lussac's Law. Gay-Lussac's Law states that the volume of an ideal gas is directly proportional to its temperature at constant pressure. The experiment shows how gas temperature and volume change as described by the law.