Collapse a Soda Can

DESCRIPTION:
When a small amount of water is heated inside the can, steam is produced, filling the can. When the can is inverted into cold water, all of the steam condenses quickly causing the can to implode.

TOPICS COVERED:
Charles’ Law
physical change
thermal conduction
thermal convection

MATERIALS NEEDED:
– soda can full ~1/4 of the way with water
– hot plate
– oven mitt or potholder
– large beaker mostly full of cold water

PROCEDURE:
1. heat the soda can until the water is boiling
2. using the oven mitt put the soda can into the beaker of water upside down

ADDITIONAL COMMENTS:
The soda can will make a loud pop as it is inverted and the quicker it is inverted into the beaker the better.

SAFETY:
Boiling water is involved so safety glasses should be worn and precautions should be taken to protect against burns.

REFERENCES:
Shakhashiri, B.Z. Chemical Demonstrations; University of Wisconsin Press: Madison, 1985; Vol. 2, pp 6 – 8.

STORY:
For any age, the person doing the demo could challenge the audience to come up with a way to collapse the can using only the materials set out (no smashing the can allowed).

Handout

This problem set practices calculating mass from density, manipulating the equation: q = mCΔT, calculating the heat required to vaporize water, and unit conversions.