- A flat tray (like a cookie baking tray)
- Food coloring (at least 3 different colors)
- Whole milk - low fat milk will not work for this experiment
- Liquid soap used for washing dishes
- Carefully pour the milk into the tray so that it just covers the bottom
- Add about 6-8 drops of different colored food coloring onto the milk in different spots
- Add about 5 drops of the liquid soap onto the drops of food coloring and watch the show!
- To clean up, simply pour the colored milk down the drain. (don't drink it!)
So you know where the color comes from, but why milk and liquid soap? The main job of dish soap it to go after fat and break it down. Usually the fat is on dishes from the food we eat, but fat is also in whole milk. When you drop the liquid soap onto the tray, it tried to break down the fat in the milk. While it was doing that, it caused the colors to scatter and mix creating a very colorful display. Have fun!
The project above is a DEMONSTRATION. To make it a true experiment, you can try to answer these questions:
1. What liquid dish soap works the best?
2. Does the shape of the tray affect the reaction?