Create cool fireworks in this easy experiment!
Topics: Solubility, density
Difficulty: Elementary school
1 Tall Clear Glass
Small Disposable Cup (or something similar)
1. Fill the tall glass with water
2. In a separate cup, add 2 tablespoons of oil. (Although it is a bit hard to see, there is oil in the cup below)
3. Put a few drops of food coloring in the water. Then stir this so that the food coloring drops break down into smaller bits. The smaller the droplets of food coloring are, the more complex the firework will be. However, stirring too much can cause the food coloring to mix.
4. Drop the oil mixture into the tall glass of water that was prepared earlier.
5. Watch the food coloring drop into the water as water fireworks!
Here's A Video of the Final Result!
How it works:
Since food coloring is a water-based compound, it dissolves in water, but not in oil. So, when the food coloring is added to the oil, it stays as the droplets that it was dropped in as and gets suspended in the oil.
When we add the food coloring and oil combination to the water, since oil is a less dense material than the water and food coloring, it rises to the top, while the food coloring sinks below the oil. As the food coloring sinks below the oil, it comes into contact with the water. Since food coloring can dissolve in water, once it encounters the water, it tries to dissolve in the water. As it dissolves, the color expands in the water, giving us the vibrant, firework-like patterns!