Hydrogen and chlorine gases can be mixed together without reacting, but when the mixture is struck with bright light, it reacts explosively.
The test tube is placed within the brass cannon for safety; should the explosion shatter the test tube, the metal would prevent flying glass. The hydrogen and chlorine do not react when they are just mixed together, but the reaction can be initiated by a bright light.
Credits:
- Demonstration
- John W. Moore University of Wisconsin - Madison, Madison, WI 53706
- Setup
- Lynn R. Hunsberger University of Louisville, Louisville, KY 40292
- Video
- Steven D. Gammon University of Idaho, Moscow, ID 83843
- Text
- Kelly Houston Jetzer University of Wisconsin - Madison, Madison, WI 53706
- John W. Moore University of Wisconsin - Madison, Madison, WI 53706