Which Balloon Has Hydrogen?

Air is an invisible gas as are hydrogen and helium. How can you tell if a balloon contains hydrogen? Hydrogen has particular physical and chemical properties that can be tested. Dr. Cech enlists student volunteers to show how a chemical reaction can be used to identify a substance.

5 min 55 sec
Play Large: MOV / WMV (22 MB)
Play Small: MOV / WMV (10 MB)

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