Skip to main content

Novel Coronavirus — September 22, 2021 Update: Explore Scouts Canada’s actions as we continue to follow the direction of government and health agencies in maintaining public health. View recommendations and stay informed here. Learn more about Scouts Canada's new vaccination mandate.

Elephant Toothpaste

Learn about chemical reactions as you try this experiment! What do the materials look like before, during and after this experiment?

Back to Activity Finder

Plan

  • How can you keep track of changes before, during and after this experiment?
  • What do you think is going to happen? (Guessing what is going to happen during an experiment is called a ‘prediction’ or ‘hypothesis’)
  • Will you do this experiment in pairs or small teams?
  • What supplies will you need for this experiment?

Do

  • Safety first! Start by putting on your safety glasses.
  • Place your plastic bottle in the tray or tub for easy clean up.
  • Measure ½ cup of hydrogen peroxide and pour it into the bottle.
  • Add a big squirt of dish soap to the bottle and swirl it gently to mix
  • If you want to add food colouring, add a few drops of food colouring to the bottle.
  • In a measuring cup, mix together one tablespoon of yeast and three tablespoons of warm (not hot!) water. Stir for about 30 seconds.
  • Pour the yeast mixture into the bottle then quickly step back and watch your reaction go!

Review

  • What happened when you added the yeast mixture to the hydrogen peroxide?
  • Was your prediction correct? What happened?
  • When hydrogen peroxide comes into contact with yeast, it starts breaking down into water and oxygen. Oxygen is a gas and wants to escape the liquid. The dish soap traps these bubbles and makes a foam.

Materials

  • Empty plastic bottle per pair or team
  • A stir stick that will fit through the opening of the bottle
  • Dry yeast
  • Warm water
  • Liquid dish soap
  • 3% hydrogen peroxide
  • Measuring cups
  • Measuring spoons
  • Safety glasses
  • Large tub or tray to catch the foam
  • Garbage bags to go under the tray in case of overflow
  • Liquid food colouring (optional)
  • Different-shaped bottles or glasses (optional)

Keep it Simple

  • Do this experiment as a big group or in Lodges/Lairs. Work together to measure out the ingredients carefully with the help of a Scouter.

Take it Further

  • Try changing some elements of this experiment to see what changes. What happens if you do not add the dish soap? What happens if you put the ingredients into a differently-shaped bottle