PURPOSE: To demonstrate that breaking wintergreen mints creates small flashes of light.

DESCRIPTION: Wintergreen mints are smashed IN A DARK ROOM between two glass plates, as pictured above, or by biting into one. When the mint breaks, a small flash of bluish light is produced.

When a sugar crystal in the mint is broken, it is often separated into two sections with different charges, creating a potential difference. If enough crystals are fractured simultaneously, the potential becomes large enough to cause electrons in the structure to be repulsed from one region and attracted to another. In transit, these electrons strike other electrons in nitrogen molecules in the air, raising the atomic electrons to excited states. When the electrons decay they emit ultraviolet radiation that strikes molecules of methyl salicylate flavoring in the wintergreen mint. These molecules of methyl salicylate flavoring absorb the UV radiation and re-emit it as the blue light observed when the mint fractures.

SUGGESTIONS: This demonstration must be done in a very dark room and must be viewed at very close range.


EQUIPMENT: Wintergreen mints, glass plates to smash the mints, and lots of tissues to clean up the mess (if you don't eat it).


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