Why does a Coke can filled with steam collapse in cold water?
Coke cans containing a small quantity of water are heated until the water boils. Steam (gaseous water), fills the can and pushes the air out the hole in the tops. After the can has filled with steam, it is quickly immersed in a container of ice water. Click on the small picture to see the video. The steam is cooled in the ice water and condenses to a small quantity of liquid water. Condensation of steam to liquid water creates a vacuum inside the can. Atmospheric pressure outside the can is around 760 mm Hg, while pressure inside the can is much less. The can collapses because of the pressure difference.
