Collapsing Can
Description: Water is added to an empty soda-pop can and heated to boiling. Can is then quickly inverted into cold water which causes it to collapse. Or a larger gas can is used and instead of being inverted into the water after heating the water inside, the can is stoppered and allowed to cool in water or in room temperature air.
Concept: When water vapor inside the can is cooled it condenses,
decreasing the pressure on the inside of the can. With the pressure on the
outside of the can greater than that on the inside, the can will collapse.
Materials:
 | Aluminum can (100 % Al, no steel)
| 15 mL of water
| Bunsen burner with stand and steel wire gauze
| beaker or pan full of cold water | |
Procedure:
Put a small amount of water in can and heat over Bunsen burner. When water is
boiling and water vapor escapes the can, quickly invert can into pan of cold
water.
Clean-up: Recycle aluminum can.