Video: Watch this demo
Description: Crush the can using the principles of thermodynamics.
Equipment:
- Metal can filled with 1.5cm water
- Bunsen burner, stand, and matches
- Vacuum grease
- Protective gloves
- LN2 or cold water (optional)
Setup Procedure:
- Connect the Bunsen burner to the gas line and put the stand over the burner.
- Fill the can with about 1.5cm of water.
- Put a little vacuum grease on the can cover (to form an air tight seal when you cap it).
Demonstration Procedure:
- Put the can on the stand with the cap off and light the burner.
- Wait until a steady amount of steam is boiling off. (may take 10-20 minutes)
- Turn the flame off, and cover the can with the cap tightly (use protective gloves)
- You can either let it cool off slowly, or pour some LN2 or cold water over it (LN2 or water are more effective and faster).
Concepts: This demo shows the relationship between temperature, volume and pressure of a gas. The boiling water in the can creates steam, closing the can traps the hot steam in a closed volume. The cold liquid then rapidly lowers the temperature of the steam, condensing it and causing the pressure to drop inside the can. This causes a pressure imbalance between the inside and outside of the can, allowing the much greater atmospheric pressure to decease the volume by crushing the can.
Open Flame
Keep away from flammable materials.
32-D5
