Fun Science Activities to Do with Kids in The Summer (Part 6)
Still summer (although less and less of that now), still looking for things to do with your children? Check out the first five parts of our series (1, 2, 3, 4, 5), or one of our personal favorites, below: Elephant Toothpaste!
What is elephant toothpaste, you might ask? Simple! It’s toothpaste for elephants. But for real, it’s a mixture of dish soap, yeast, and hydrogen peroxide that reacts to form a foamy substance that resembles toothpaste for somebody (or something) with very large teeth.
How do you do this? First put hydrogen peroxide in the bottom of an empty 16-ounce soda bottle (½ cup of a 20-volume hydrogen peroxide liquid, available from a beauty supply store), then add a few squirts of dish soap and food coloring of your choice. In a separate container, mix one packet of dry yeast and three tablespoons of warm water. This is called “proofing” the yeast, and helps the fungi spores start to grow again. Finally, add the yeast mixture to the soda bottle and watch the foam form!
Where can I find 20 volume hydrogen peroxide? 20-volume is a concentration notation that is the same thing as the 6% solution. You can buy 8% from Amazon.com, or use Salon Care Professional Stabilized Formula or 20 Volume Clear Developer from Sally Beauty Supply. In addition to hydrogen peroxide, you can use concentrated bleach instead.
*Note that hydrogen peroxide and bleach can both be an irritant in a variety of different ways. Use carefully and in a well-ventilated area. Check out the safety precautions on hydrogen peroxide HERE and the precautions for bleach HERE.
What is the science? The hydrogen peroxide breaks down into water and oxygen, and the addition of yeast enables that reaction to go faster (catalyzes the reaction), and makes more oxygen bubbles form quicker. When the oxygen form in the presence of dish soap and food coloring, lots of foamy elephant toothpaste is the result!
Note that you can also use potassium iodide instead of yeast: https://chemdemos.uoregon.edu/demos/Elephants-Toothpaste; which may be a good option for some of you (if this chemical is more easily available, I guess, although I assume most people can find dry yeast packets fairly easily.
Have you tried this at home? Let us know how it turns out!