more in 10-12 years
FANTASTIC FOAMY FOUNTAIN
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You will need
- A clean 16 ounce (473 ml) plastic soda bottle or a water bottle.
- 20-Volume hydrogen peroxide liquid (20-volume is a 6% solution that is stronger than what you find in most pharmacies. It is typically used for lightening hair and is found at many beauty supply stores. You can use the 3% hydrogen peroxide found in pharmacies, but the reaction will be a bit smaller)
- 1 Tablespoon (15ml – one packet) of dry yeast
- 3+ Tablespoons (15 ml) of warm water
- Liquid dishwashing soap
- Food coloring
- Small cup
- Funnel
- Safety goggles
- Adult help
NOTE: The foam could overflow from the bottle, so be sure to do this experiment on a washable surface, or place the bottle on a tray.
CAUTION: The unreacted hydrogen peroxide can irritate skin and eyes. Read the safety information on the hydrogen peroxide bottle and be sure to wear safety goggles.
What to do
- Use a funnel to carefully pour 3/4 cup (180 ml) of the hydrogen peroxide liquid into the bottle
- Add about 10 drops of your favorite food coloring into the bottle.
- Add about 1 tablespoon (15ml) of liquid dish soap into the bottle and swish the bottle around a bit to mix it.
- In a separate small cup, combine the warm water and the yeast together and mix for about 30 seconds. It should be about the consistency of melted ice cream – add a bit more warm water if needed.
- Now the adventure starts! Use the funnel to pour the yeast-water mixture into the bottle and watch the foaminess begin!
Can I touch the
foam?
The reaction typically breaks down the hydrogen peroxide so you are left with mostly just soapy water and yeast. There can, however, be un-reacted peroxide which could irritate skin and eyes. For that reason, it is recommended you do not touch the foam.
(If you use the 3% hydrogen peroxide found in most pharmacies, then the foam can be touched safely.)
How does it work?
Foam is awesome! The foam you made in this classic Elephant’s Toothpaste reaction is extra-special because each tiny foam bubble is filled with oxygen. The yeast acted as a catalyst; a catalyst is used to speed up a reaction. It quickly broke apart the oxygen from the hydrogen peroxide. Because it did this very fast, it created lots and lots of bubbles. Did you notice the bottle got warm? Your experiment created a reaction called an Exothermic Reaction – that means it not only created foam, it created heat! 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.
This experiment is sometimes called “Elephant’s Toothpaste” because it looks like toothpaste coming out of a tube, but don’t get the foam in your mouth!
Make it an experiment:
The project above is a DEMONSTRATION. To make it a true experiment, you can try to answer these questions:
- Does the amount of yeast change the amount of foam produced?
- Will the experiment work as well if you add the dry yeast without mixing it with water?
- Does the size of the bottle affect the amount of foam produced?
Science Bob
How to Make Steve Spangler’s Hydrogen Peroxide and Soapy Yeast Foaming Reaction
Elephant Toothpaste Experiment Recipe at Steve Spangler Science
Looking for the elephant toothpaste formula recipe? You’ve come to the right place! Here is where you’ll get our easy-to-follow, step-by-step instructions about how to make the world-famous Steve Spangler’s hydrogen peroxide and soapy yeast foaming reaction formula — also known as the Elephant Toothpaste Experiment!
Elephant Toothpaste Formula: A Steve Spangler Science Exclusive
Learn how to make Steve Spangler’s Elephant Toothpaste recipe using safe and easy materials you can find at home. Only a few ingredients are necessary to make a BIG impression on your kids or your students. For variables, use different percentages of hydrogen peroxide to see how this single ingredient affects the overall foam-tastic explosion! You can also add food coloring for multi-color elephant’s toothpaste foam that is guaranteed to WOW your kids. For a fabulous, Halloween-inspired twist on this experiment, check out our Oozing Pumpkin Elephant’s Toothpaste Experiment for this memorable hands-on experiment that was featured on the Ellen DeGeneres Show! Kids: Go get a great adult helper, grab your ingredients (be sure to put on your safety glasses — we always should practice safe science) and watch the explosions begin!
Experiment Materials
- 1-liter plastic soda bottle
- Hydrogen peroxide (12%) (This is found at a store that sells hair care products. Ask for hydrogen peroxide that is labeled 40-volume. This is the same as a 12% solution.)
- Liquid dish soap
- Food coloring
- Package of dry yeast (found at the grocery store)
- Measuring spoons
- Funnel
- Construction paper, markers, and some creativity
- Safety glasses
- Plastic tarp to cover the demonstration table
- Rubber gloves
Experiment Videos
Experiment
1
Let’s start with the arts and crafts part of the activity by making a decorative wrap to cover the plastic soda bottle. Since the activity is called Exploding Toothpaste, use your creativity to make a wrap that looks like a tube of toothpaste.
2
Put on your safety glasses and rubber gloves.
3
Cover the demonstration table with the plastic tarp.
4
Use a funnel to add 4 ounces (120 mL) of 40-volume hydrogen peroxide to the 1-liter soda bottle.
5
Add a squirt of dish soap and some food coloring to the hydrogen peroxide in the bottle. Give the solution a quick swirl to mix the contents.
6
Carefully cover the bottle with the toothpaste wrap that you made previously. It’s best to have someone help you with this step to prevent you from accidentally tipping over the bottle.
7
The next step is to prepare a kid-friendly catalyst for the reaction by mixing an entire package of dry yeast with 4 tablespoons of very warm water in a small plastic cup. Stir the mixture with a spoon. If the mixture is too thick or paste-like, add a small amount of warm water to thin it out.
8
Here comes the fun part. Pour the yeast mixture into the bottle and watch what happens. It may take a few seconds to react, but the result is well worth the wait.
When you are finished, it is safe to dispose of all of the demonstration materials either by throwing them away in the trash can or by washing them down the drain.
How Does It Work
Similar to what happened in the adult version of Exploding Toothpaste, the yeast works as a catalyst to release the oxygen molecules from the hydrogen peroxide solution. The oxygen-filled bubbles, which make up the foam, are actually the remainder of what happens when the hydrogen peroxide breaks down into water (H2O) and oxygen (O2). The bottle will feel warm to the touch because this is an exothermic reaction in which energy, in the form of heat, is given off.
Steve Spangler Science
Love our Elephant Toothpaste Experiment? Don’t miss our other experiments in our HUGE online experiment library. For all-in-one kits, check out our science kits and our at-home science experiments. For over 25 years, Steve Spangler Science has been on a mission to inspire kids and get them excited about STEM subjects. Our experiments and science-themed products are fantastic for after-school activities, activities for summer break or classroom activities that will amaze kids of all ages!