Glowing Water: The Science of Fluorescence at Home
Educational and Fun Activities
Written by Gregg Payne
28 August 2024
🕓 4 min
What if you could make water glow? With a simple experiment, you can introduce your child to the fascinating world of fluorescence. This glowing water activity is fun, easy to do at home, and a fantastic way to explore how certain substances react to light. By using items you might already have around the house, you’ll create glowing water and learn the science behind it. Let’s dive into how to make water glow and discover the magic of fluorescence!
1. What You’ll Need
- A clear container or glass of water
- A highlighter (preferably yellow)
- A black light (UV light)
Step-by-Step Instructions
- Prepare the highlighter ink: Take apart the highlighter by carefully pulling off the back end (you may need an adult to help with this part). Inside, you’ll find a felt tube filled with ink. Carefully remove the felt and squeeze it into the water, or simply dip the tube into the water until the ink spreads and dissolves.
- Stir the water: Stir the water gently until the ink is fully mixed, turning the water a bright colour (usually neon yellow or green, depending on the highlighter).
- Turn off the lights: For the glowing effect to work, you’ll need a dark room. Turn off the lights to create a dim or dark environment.
- Shine the black light: Turn on the black light and shine it on the container of water. You’ll see the water glow in a vibrant colour!
2. How Does Fluorescence Work?
The glowing effect you see is caused by fluorescence. Here’s how it works:
- Fluorescence is the process where certain substances absorb ultraviolet (UV) light and then emit visible light. The ink in highlighters contains chemicals that fluoresce under UV light, making the water appear to glow in the dark when exposed to the black light.
- Ultraviolet light is a type of light that is invisible to the human eye. When the highlighter ink absorbs this light, it emits visible light, which is why we can see the glowing effect.
This experiment is a simple way to show how different materials react to UV light, introducing children to a key scientific principle used in everything from forensic science to the colourful lights you see at parties!
For another fun experiment with chemical reactions, check out our post Homemade Slime: A Polymer Experiment.
3. Exploring Further: Fluorescence in Nature
Fluorescence isn’t just something you see in highlighters—it's also common in nature! Here are a few examples of natural fluorescence:
- Jellyfish: Certain species of jellyfish glow in the dark due to fluorescent proteins in their bodies. Scientists have even used these proteins in medical research to study cells.
- Minerals: Some minerals, like fluorite, will glow under UV light. This property has been used to identify minerals and study geological formations.
- Scorpions: Scorpions have a natural fluorescence, meaning they glow under UV light. It’s believed this might help them avoid predators or communicate with each other.
4. Fun Fact About Fluorescence
Did you know that money glows under UV light? Many banknotes contain fluorescent fibres or strips that only show up when exposed to UV light. This is one of the ways banks and shops check for counterfeit bills!
Tips for Success
- Experiment with different colours: While yellow highlighters usually work best, try other colours of highlighters to see if they glow as well. You can also try tonic water, which contains quinine—a chemical that fluoresces under UV light!
- Make glowing art: If you have more black lights and highlighter pens, use them to create glowing art on paper. Draw pictures or write messages that glow in the dark when you turn on the UV light.
5. Safety Precautions
While creating glowing water is generally safe, it's important to take some precautions:
- Use non-toxic highlighters if possible.
- Handle highlighter ink carefully to avoid stains on skin or surfaces.
- Avoid ingesting any solutions created during this experiment.
Final Thoughts
Making glowing water is a simple yet exciting way to explore the science of fluorescence and the interaction between UV light and certain substances. It’s a fun experiment that teaches children about light, energy, and the fascinating ways materials can react to invisible forms of light. Plus, the glowing effect never fails to impress!
If your child loves science experiments like this, our Science of Sound holiday camps offer even more opportunities for hands-on learning and STEM-based fun. Discover more about our upcoming camps here, and give your child the chance to explore science in an interactive and engaging environment!
