Homemade Lava Lamp


Create your own temporary lava lamp with just a few everyday household items. This makes for a super easy, fun and colourful science experiment for children to try in the kitchen!

The Science:

Water is heavier than oil as its molecules are packed together more tightly. These two liquids are also immiscible, meaning they can’t be mixed together. So, when putting the two together, water will always sink below oil.

When you add baking soda to water, it reacts to form carbon dioxide gas. In this particular experiment, the carbon dioxide sticks to the water and bubbles float to the top, before popping to release the gas into the air.


  1. Fill the water bottle with vegetable oil until around ¾ full.
  2. Top up the remaining ¼ with water. The water will sink under the oil to the bottom of the bottle.
  3. Add a few drops of food colouring into the mixture – this will also sink to the bottom as food colouring is water-based.
  4. Add a tablespoon of baking soda into the bottle and stand back to watch the reaction. You’ve created your very own lava lamp!
  5. To extend the reaction, simply add more baking soda.


Prep time: 10 Minutes

Cook time: N/A

Serves: 0

  • Clear water bottle

  • Vegetable oil

  • Water

  • Food colouring

  • Baking soda