Hate Peeps? Send them to outer space. This vacuum chamber replicates the conditions of space and removes all the air and gas around an object. That means the object's molecules are no longer being combatted by outside forces. Marshmallows have a lot of tiny bubbles inside of them, and the loss of pressure causes them to expand. They eventually grow so much that they burst. Without those air bubbles, the marshmallow shrivels when air is reintroduced into the chamber. - This is a video collaborati