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.
Instructor must provide mints.