About the Activity

Chemical reactions are all around us. In this fun chemical reaction experiment, kids will learn firsthand how they work as they create a colorful foaming fountain of bubbles by adding yeast to hydrogen peroxide.


Grades: Pre-K – 2
Topic: Chemistry
Estimated Time: 20 minutes


Brought to you by HughesNet and The Ohio State University Extension

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Some of these you’ll have at home, some you may need to order or get from a hardware store.

Pantry Supplies

  • One 20oz ounce bottle (rinsed out and dry)
  • Dish soap
  • Food coloring
  • ¼ cup warm water
  • Small bowl
  • Funnel (or make one by rolling a sheet of paper)
  • Large rectangular baking pan (this keeps the mess minimal)
  • Measuring cup


Specialty Supplies

  • ½ cup hydrogen peroxide, 3% or 6% solution *Do not use solutions greater than 6%*
  • 1 packet active dry yeast


Optional Add-Ons

  • Additional 20 oz bottles of both 3% and 6% hydrogen peroxide can be used to make the project more challenging.
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Activity Steps

Before you start, get ready: You’re about to see an exothermic reaction – that is, a chemical reaction that gives off heat.

  1. Combine the warm water and yeast in a bowl and set aside for now.Did You Know? In this experiment, the yeast is going to act as a catalyst. A catalyst is a material that speeds up reactions but doesn’t react, itself.
  2. Place the bottle on the baking pan (this helps to keep from making a mess in case anything spills).
  3. Using the funnel, pour the hydrogen peroxide into the bottle.Did You Know? Hydrogen peroxide (H2O2) is made of two hydrogen atoms and two oxygen atoms. It has one more oxygen atoms than water (H2O).

  1. Add in a few drops of food coloring.
  2. Add a couple squirts of dish soap.
  3. Use the funnel to pour the water/yeast mixture into the bottle. Take the funnel out quickly, then stand back and watch what happens!Check it Out: If you touch the bottle or foam after the reaction starts, you will notice that it is warmer than when you started – that is your exothermic reaction! The heat is caused by the breakdown of hydrogen peroxide into its base elements, hydrogen and oxygen. Usually this chemical reaction happens slowly over time, but when you add the yeast- a catalyst – it speeds up the process, amplifying the affects. The oxygen that is released by the process combines with the dish soap to make lots of foam!
Bonus Fun: Set up bottles using different colored dyes. Experiment with different amounts of hydrogen peroxide (3% and 6% ) and different amounts of yeast. Make observations and compare the reactions!

Reflection Questions
Questions to deepen wonder and understanding.

  1. What did you observe before adding in the water and yeast mixture?
  2. What changed when you added in the water and yeast mixture?
  3. What do you notice if you touch the bubbles?
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Investigate and Explore
Take your new knowledge to the next level.

Chemical reactions are the scientific process in which one or more substances are converted into a different substance. And chemical reactions are all around us: wood burning in a fireplace, food cooking in a frying pan, cars burning gasoline, metal rusting, leaves rotting – these are all examples of chemical reactions. Very often, something changing color or giving off an odor – or both – are indications of a chemical reaction. And, as you can tell from the examples above, chemical reactions are important because they are a part of the world in which we live, and understanding them helps us understand the world around us.

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