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Elephant’s Toothpaste

  • 16 oz plastic soda bottle
  • 1/2 cup of hydrogen peroxide liquid (3% available in most stores will work but 6% from a beauty supply store works better)
  • 1 Tablespoon (one packet) of dry yeast
  • 3 Tablespoons of warm water
  • Liquid dish washing soap
  • Food coloring
  • Small cup
  • Flat pan or tray


  1. Place the bottle on the flat pan or tray.
  2. Pour the hydrogen peroxide into the bottle.  **Warning hydrogen peroxide can irritate  your skin and eyes, so ask an adult to help.
  3. Add several drops of your favorite color of food coloring
  4. Add a large squirt of liquid dish soap
  5. In the small cup mix the yeast and warm water together.
  6. Pour the yeast mixture into the bottle and watch what happens.

What’s going on?

Hydrogen peroxide chemical formula is H2O2; which is like water, H2O, with an extra oxygen, O.  The yeast acted as a catalyst to remove oxygen.  This oxygen gas is leased rather quickly and gets caught up in the soap bubbles…of foam.  You may also notice that the bottle is warm to the touch.  That because the reaction also gave off some heat, as well as oxygen.  This is called an exothermic reaction.

Source: Science Bob’s Fantastic Foamy Fountain


300 S Tulane,
Oak Ridge, TN 37830
Phone: (865) 576-3200


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Sunday: 1 - 5 pm

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