Question: How Do Glow Sticks Glow?

Megan Seymour answered on 9 Nov 2016:

That’s a great question!
Inside the plastic glow stick there is a thin glass container that breaks when you bend the plastic. When the glass container is broken, two chemicals can mix.
Usually these two chemicals are hydrogen peroxide (the same chemical that is in normal bleach) and a chemical called phenyl oxalate ester. When these chemicals react they give off energy.
In a lot of chemical reactions, energy is given off in the form of heat energy.
What makes a glow stick different is a third chemical- called a fluorescent dye. A fluorescent dye is a molecule containing metal atoms that is able to absorb energy. The energy is given to electrons within the molecule. These high energy electrons aren’t stable so want to get rid of their extra energy. They do this by giving off the energy as light – and that’s how the glow stick glows.
The colour of the light just depends on the exact chemical formula of the fluorescent dye.

I hope some of that makes sense, if not, write a comment and I’ll try to explain a bit better!