Aquatic fireworks

Procedure

• Fill the 100 mL precipitation beaker halfway with water.
• In the other precipitation beaker, mix a little oil with a couple of drops of food coloring and stir.
• Finally, add the oil mixture to the precipitation beaker containing water and observe what happens.

Theoretical explanation

The food coloring is not soluble in oil but it is soluble in water. When it is added to the mixture, the drops descend through the oil as spheres and then stay in the interphase of both liquids. After some time, the food coloring falls into the water phase and diffuses forming the aquatic fireworks.