
Make glowing water with the help of a black light in this fun science experiment for kids. Tonic water doesn't look very strange under normal light but what happens when you look at it under a black light? Does the dye from a highlighter pen do the same thing? Find out what happens and why it happens with this cool experiment that you can do at home.
What you'll need:
v A black light
v Tonic water or a highlighter pen
v A dark room to do the experiment
Instructions:
1. If you are using a highlighter pen carefully break it open, remove the felt and soak it in a small amount of water for a few minutes.
2. Find a dark room.
3. Turn on the black light near your water, how does it look?
What's happening?
The ultra violet (UV) light coming from your black light lamp excites things called phosphors. Tonic water and the dye from highlighter pens contain phosphors that turn UV light (light we can't see) into visible light (light we can see). That's why your water glows in the dark when you shine a black light on it.
Black lights are used in forensic science, artistic performances, photography, authentication of banknotes and antiques, and in many other areas.