Try This: Elephant Toothpaste

The Goodman Center elementary Girls Inc. participants were recently treated to an extra fun, extra messy (that just adds to the fun) STEM activity: Elephant Toothpaste. STEM Coordinator Rachel shared the how-to in case you want to recreate this one at home.

This experiment is called Elephant Toothpaste because it looks like toothpaste coming out of a tube – but don’t get the foam in your mouth! Be careful when touching the foam and bottle – and make sure to wear gloves. You’ll notice the bottle will get warm. This is because you’ve created a reaction called an exothermic reaction. That means not only did this experiment create foam, it created heat.

You will need:

• Empty plastic water bottle
• 3-6% hydrogen peroxide
• 1 tablespoon/2 squirts of dish soap
• Food coloring
• 1 tablespoon dry yeast
• Safety goggles and gloves
• 3 tablespoons of warm water

How to make it:

1. Put on your googles and gloves, and set up in an area where it's safe to spill. Use a tablecloth or go outside.
2. Using a funnel, pour about 3/4 cup of hydrogen peroxide in the empty water bottle.
3. Add 3 drops of food coloring into the bottle.
4. Add 1 tablespoon of dish soap and swish the bottle around a bit to mix it.
5. In a separate bowl, add yeast and warm water. Tip: Your water needs to be warm to activate the yeast, but make sure it’s not hot. Water that is too hot will kill the yeast.
6. Let the yeast sit in the warm water for 1 minute.
7. Using a funnel, pour the yeast and water mixture into the bottle containing the soap and peroxide mixture.
8. Sit back and watch the foamy fun!

Cleaning up:

The foam produced is just water, soap and oxygen so you can clean it up with a sponge and pour any extra liquid left in the bottle down the drain.