Collapsing Can: Gas Laws Atmospheric Pressure
A demonstration of the large force of atmospheric pressure, 14.7 lbs/in2.
For option 1, the soda/pop can, as the can cools, the water vapor in the can also cools and condenses causing a decrease in pressure within the can. Because the can is sealed, there is a decrease in pressure of air inside the can. The pressure of the atmosphere acting on the walls of the can exerts a force that is not countered by the air pressure within the can. The difference in pressure causes the can to collapse.
On-line videos of this demonstration
Option 1
Soda/Pop Can
10 mL of water
Hot plate to heat/boil the water
Tongs
Wide container capable of holding about 500 mL of water
Ice
Heat resistant gloves
Option 2
Vacuum pump
Metal gas can
Rubber stopper with glass tubing to fit can
Rubber tubing and connection
Option 1 (Soda/Pop Can)
- Place the water in the can.
- Place the can on the hot plate.
- Heat the water in the can until it fills with water vapor.
- Use the tongs, remove the can from heat and invert it, placing the opening in a shallow container of water.
- The can will collapse immediately.
References:
1. L. Summerlin, C. Borgford, J. Ealy; Chemical Demonstrations: A Sourcebook for Teachers; 1987; Volume 2; P.89
2. B.Z. Shakhashiri. Chemical Demonstrations: A Handbook for Teachers of Chemistry; Wisconsin; 1985; Volume 2; p. 6-8
