You will need:
- A jar
- Fizzy tablet (Alka-Seltzer, vitamin tablet or similar)
- Food colouring (colour of your choice)
- Half-fill the jar with water
- Add a few drops of food colouring
- Fill the rest of the jar with oil
- Allow a few minutes for the oil and water to separate
- Drop the fizzy tablet and watch the show begin!
The science bit:
- Oil is less dense than water, so the oil sits on top of the water.
- The fizzy tablet reacts with the water and creates bubbles of carbon dioxide. The carbon dioxide wants to escape so it travels upwards, taking the bubbles of water through the oil and creating a cool effect!
Why not try:
- Making a few that are different colours – a lava lamp disco!
- Trying some different liquids and seeing if it creates a different effect.