WEBVTT - Why do Wint-O-Green Life Savers spark in the dark?

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<v Speaker 1>Welcome to Brainstuff from house Stuff Works dot com where

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<v Speaker 1>smart Happens. Hi Am Marshall Brain with today's question, why

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<v Speaker 1>do win a green Life Savers spark in the dark? Actually,

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<v Speaker 1>any hard sugar based candy will emit some amount of

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<v Speaker 1>light when you bite on it, but most of the

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<v Speaker 1>time that light is extremely faint. This effect is called

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<v Speaker 1>tribo luminescence. It's the admission of light that happens when

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<v Speaker 1>something is being smashed or torn. When you rip a

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<v Speaker 1>piece of tape off the roll, it will produce a

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<v Speaker 1>slight glow. For the same reason, tribo luminescence occurs when molecules,

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<v Speaker 1>in this case crystalline sugars, are crushed. This forces some

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<v Speaker 1>of the electrons out of their atomic fields. These free

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<v Speaker 1>electrons bump into nitrogen molecules in the air, and when

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<v Speaker 1>they collide, the elector drowns impart energy to the nitrogen molecules,

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<v Speaker 1>causing them to vibrate. In this excited state, these nitrogen

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<v Speaker 1>molecules emit light, mostly ultra violet light that's not visible,

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<v Speaker 1>but they do emit a small amount of visible light

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<v Speaker 1>as well. This is why all hard sugary candies will

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<v Speaker 1>produce a faint glow when cracked, but when you bite

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<v Speaker 1>into a winter Green lifesaver, a much greater amount of

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<v Speaker 1>visible light can be seen. This brighter light is produced

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<v Speaker 1>by the winter green flavoring itself. Methyl salicillate or oil

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<v Speaker 1>of winter green, is fluorescent, meaning it absorbs light of

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<v Speaker 1>a shorter wavelength and then emits it is light of

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<v Speaker 1>a longer wavelength. Ultra Violet light has a shorter wavelength

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<v Speaker 1>than visible light, so when a winter green lifesaver is

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<v Speaker 1>crushed between your teeth, the methyl salicillate molecules absorb the

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<v Speaker 1>ultra violet shorter wavelength light produced by the excited nitrogen

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<v Speaker 1>and then re emit it as light in the visible spectrum,

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<v Speaker 1>specifically as blue light. Thus you see blue sparks when

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<v Speaker 1>you crunch on a winter green light saver. So you

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<v Speaker 1>can try this out yourself. Grab some lifesavers, go to

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<v Speaker 1>a pitch black room or closet with a friend and

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<v Speaker 1>see what happens. Maybe some sparks will fly. Do you

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<v Speaker 1>have any ideas or suggestions for this podcast? If so,

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<v Speaker 1>please send me an email at podcast at how stuff

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<v Speaker 1>works dot com. For more on this and thousands of

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<v Speaker 1>other topics, go to how stuff works dot com and

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