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Author Topic: What happens when you snap a glowstick to make it glow?  (Read 1808 times)

Offline thedoc

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When you snap a glowstick, what makes it glow?          
Asked by Catherine in Ashwell


                                        Visit the webpage for the podcast in which this question is answered.

 

« Last Edit: 28/09/2013 18:24:41 by _system »


 

Offline thedoc

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What happens when you snap a glowstick to make it glow?
« Reply #1 on: 28/09/2013 18:24:41 »
We answered this question on the show...

It's           luminol, or a dye like it, that you're activating.
This is a chemical that can absorb chemical energy and then release it as visible light.
In a glowstick, the chemical reaction that energises the luminol is usually the oxidation of an ester, called phenyl oxalate, by hydrogen peroxide (H2O2) in the presence of a strong alkali, like sodium hydroxide (NaOH).
If all of these chemicals were present in the same tube when the glowstick was manufactured, they would begin reacting immediately and, by the time you needed it, the glowstick would be exhausted.
Instead,the chemicals are kept apart by putting the luminol and the ester and the alkali in one tube and the peroxide into a separate tube, usually made of thin glass, which is floating inside the tube containing the luminol. 
This means that the reaction will only begin when you break the glass by bending the glowstick and allowing the chemicals to mix.
« Last Edit: 28/09/2013 18:24:41 by _system »
 

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What happens when you snap a glowstick to make it glow?
« Reply #1 on: 28/09/2013 18:24:41 »

 

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