- A clean 16 oz soda bottle or beaker (should be clear for best results)
- 1/2 cup of hydrogen peroxide (6% solution works best, but any will do)
- 1 tablespoon dry yeast (approx. 1 yeast packet)
- 3 tablespoons warm water
- Liquid dish washing soap
- Small cup
- Food coloring
What To Do:
Combine yeast packet with warm water in the small cup. The sooner this is done the better the results will be. This gives the yeast time to activate.
- Add 8-10 drops of food coloring into the bottom of the soda bottle or beaker.
- Add 1-2 tablespoons of dish washing soap into the food coloring in the soda bottle or beaker. Swirl.
- Finally, pour the yeast and warm water mixture into the soda bottle or beaker (a funnel works well for this step).
Foaming should begin immediately and rapidly.
Location and Appropriate Age Group:
- This demonstration tends to make a mess but is not harmful. It is best done outside if possible either on concrete or a sidewalk, or somewhere where it can be easily rinsed with a hose. If this demonstration is done inside, tile floor is best, and in a larger bin so as not to spill it on the floor.
- Elephant Toothpaste is a great demonstration for all age groups.
How It Works:
- The foam consists of thousands of oxygen filled bubbles.
- In this demonstration the yeast acts as a catalyst in removing all the oxygen from the hydrogen peroxide. This demonstration creates an exothermic reaction. The soda bottle or beaker should feel warm to the touch after the yeast is added.
- The foam itself is simply oxygen, water and soap so it is non-toxic.
It is called elephant toothpaste because it should resemble large toothpaste coming out of a tube.