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Make your own bath bomb!


Make your own bath bomb!

(Suitable for secondary school children and above)

In this activity you will investigate how to make your own bath bomb! We can all support the diversity of our planet by using less packaging including single-use materials.

By designing your own bath bomb you could also find a way to cut down on the packaging required and encourage others to make their own bath bombs.

What you need: Dry ingredients: 100 grams baking soda, 50 grams citric acid, 25 grams cornflour, Wet ingredients: 2 tbsp sunflower oil or olive oil, 2 tsp water, 1 tsp food colouring (optional), 12-15 drops essential oils of choice (be sure to check for allergies), Kit list: two mixing bowls, whisk, flexible plastic moulds (clean empty yogurt pots, silicone ice cube tray or silicone cupcake cases)


  1. Mix the dry ingredients together in one bowl and the wet ingredients together in the other bowl.
  2. Add the wet ingredients to the dry ingredients a few drops at a time while whisking, until the mixture just sticks together when pressed.
  3. Press the mixture into the mould and leave to dry for at least 2 hours.
  4. Make a few bath bombs with variations and record the differences in them, such as: More or less baking soda, More or less citric acid, Different oils (citric or other), Different colours
  5. Remember to keep some elements the same, to make it a fair test.
  6. Now it’s time to test your bath bomb! Put the bath bomb in some water and record: How long it takes to disperse? How high the ‘fizz’ is? What happens to the water? Anything else you think might be important in deciding if a bath bomb is effective or not?
  7. Compare your different bath bombs, deciding which one makes it more effective as a bath bomb.

Caitlin Brown, British Science Association

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