Elephant Toothpaste

Here’s another acid-base experiment along the same lines as the homemade volcano. The reaction here is a bit simpler, but there is an extra ‘hot’ part to teach the kids something. Let’s make elephant toothpaste!

What You Will Need

– 2-liter bottle
– cookie sheet or roasting pan (to catch the mess!)
– 1 teaspoon yeast
– 2 tablespoons warm water
– ½ cup 6% plus hydrogen peroxide
– food coloring
– one tablespoon dish soap

What You Will Do

Start by preparing the 2-liter bottle in the pan. In a separate container, mix the warm water and yeast together thoroughly. Set this aside for a moment.

Now, in the 2-liter bottle, mix the hydrogen peroxide, 4-5 drops of food coloring and a healthy squirt of dish soap.

You’re all set- add the yeast and water mixture to the 2-liter bottle and watch the reaction go!

For extra credit, feel the foam and 2-liter bottle as the reaction happens- it’s warm. How crazy is that?!

Watch a video of this experiment in action here.

What is Going On?

Similar to the home volcano experiment, a chemical reaction is happening here. But there are a few key differences.

For starters, this is actually a natural process. Hydrogen Peroxide breaks down over time into water and oxygen [ 2H2O2 -> H20 + O2]. This is why you won’t find it in a clear container- light accelerates this process.

What makes this reaction go is the yeast. Catalase, a component in yeast, speeds up the reaction- i.e., acts as a catalyst. The dish soap is there to capture the oxygen as it is released and make the bubbles. This process also releases energy which heats the foam and container. This is an example of an exothermic reaction.

Want a kit that makes this even easier? Get it here: