A glow stick is pretty cool invention when you think about it. It gives us light without needing to be plugged in. It also doesn’t use any batteries. Everything that the glow stick needs to glow is right there inside of it!
There is a special chemical reaction that makes it happen. Inside the glow stick there is a liquid chemical and some dye, but when you first take a glow stick out of its package, they aren’t doing much. Nothing is glowing yet.
Inside the glow stick, there is also another smaller tube that is made of a very brittle material, like glass. That smaller tube holds another chemical inside it. That way, the chemicals stay separated. What do you think happens when the chemicals mix?
By bending the glow stick, we actually break the smaller tube on the inside. You usually will hear a tiny crack when this happens. The chemical inside the smaller tube leaks out and mixes with the other chemical on the outside.
A new chemical is formed, and it’s an unstable one, meaning that it can’t keep itself together very well. As the new chemical breaks down, it gives off energy that excites the atoms of the dye. When this happens, the glow stick lights up!