Elephant’s Toothpaste - Kid Version
This is a kid-safe version of the popular Elephant's Toothpaste demonstration using common household materials. A child with a great adult helper can safely do this activity and the results are wonderful.
- 16 oz empty plastic soda bottle (preferably with a narrow neck such as those made by Coca-Cola)
- 1/2 cup 20-volume hydrogen peroxide (20-volume is 6% solution, purchased from a beauty supply store)
- Squirt of Dawn dish detergent
- 3-4 drops of food coloring
- 1 teaspoon yeast dissolved in approximately 2 tablespoons very warm water
- Foil cake pan with 2-inch sides
- Safety glasses
- Lab smock
- Have students put on their safety glasses and lab smock. Each student should have in front of them a cake pan, plastic bottle, Dawn in small cup, food coloring, 1/2 cup peroxide, and the dissolved yeast mixture.
- Stand the bottle up in the center of the cake pan. Put the funnel in the opening. Add 3-4 drops of food coloring to the peroxide and pour the peroxide through the funnel into the bottle. Show a water molecule diagram and a peroxide molecule diagram, pointing to the extra oxygen that will be set free in the reaction.
- Add the Dawn detergent to the peroxide in the bottle.
- Pour the yeast mixture into the bottle and quickly remove the funnel.
- The students can touch the bottle to feel any changes that take place.
How Does It Work?
Talk about the addition of the yeast as a catalyst, which makes the peroxide molecule release the oxygen atom faster. The teacher who submitted this experiment claims to have done this with hundreds of students from kindergarten through fifth grade and some adults who all loved the experiment. It is very easy and safe to do again at home using regular hydrogen peroxide from the drugstore.
The reaction creates foam that shoots up out of the bottle and pools in the pan. After a minute or so, it begins to come out in a moving stream that looks like toothpaste being squeezed out of a tube. The students can play with the foam as it is just soap and water with oxygen bubbles. The bottle will feel warm to the touch as this is an exothermic reaction.
- Prepare yourself for a loud group of kids! Review by Matt
I did this with my K-2 science class. I used 40-volume hair developer (12% H2O2) from a beauty supply store. The first time we tried the experiment nothing happened! In a panic, I added more yeast (not dissolved) directly into the bottle and only then the reaction took place. We tried again with a second bottle. This time, after adding the H2O2, food coloring, and soap, we added the yeast WITHOUT water, placed a hand over the bottle opening, gave it a quick swirl, and PRESTO- blue toothpaste, followed by cheering/screaming 5, 6, and 7 year-olds.
I have no clue why it didn't work the first time, but I suggest you try both ways and see what works best.
(Posted on May 17, 2012)
- Fun for Cub Scouts! Review by Richard Uchytil
Today my Cub Scout Den did this. They had a great time mixing things together then making the reaction happen. Of course being boys, they then played in the foam, mixing each others together, etc. Fun times! I'd definitely recommend this to anyone!
Seeing how the other more explosive version used potassium iodide, I tried using that instead of yeast. It didn't do anything. I put the cap back on the bottle so it wouldn't spill and 30 minutes later there was foam in it AND an amazing amount of pressure! Very carefully I unscrewed the lid and it had a nice BOOM! The kids LOVED it! But I wouldn't ever let kids do that, the lid went flying fast and could easily hurt someone.
(Posted on June 6, 2012)
- Big mess, big fun! Review by hollyml
I did this experiment with 20 fourth-graders at a birthday party, and they thought it was very cool. Rather than give each kid a cake pan, we just had them all sit around the edges of a big plastic sheet on the ground, and let the foam spill out on that. They enjoyed playing with it and most of the mess was cleared away simply by picking up the plastic sheet.
Instead of supplying 20 funnels, we dissolved the (pre-measured) yeast in little paper cups (the kind meant to hold candy party favors), using popsicle sticks to stir. The kids were able to pour the contents of the little cup right into the bottle by pinching the edge of the cup to form a spout.
We used drugstore hydrogen peroxide (3%) which results in a less dramatic eruption than the higher-strength stuff, but it does work. I could not find a source for more concentrated solution, other than "food grade" which can be ordered online but was expensive and would have taken too long to ship to me. I even bought a jug of what claimed to be 29% H2O2 from a local hydroponics supply store, but it did not work -- when we tested it foamed only a little, not even enough to reach the top of the bottle. Although my science-teacher friends were happy to speculate, nobody could tell me for sure why it didn't work. (I guess I'll use the rest of the jug for cleaning something...)
Ah well, at least the 3% drugstore version is cheap! Which is good, given that I needed a lot of it. And the effect was impressive enough for this group of kids.
(Posted on March 23, 2011)
- elephant's toothpaste Review by sdearman
My 2nd grader performed this at his school for "nutty professor" day. It was very cool!
(Posted on October 15, 2009)
- Loads of Fun! Review by Phill
I did this experiment with my daughter, and she loved it. It's fun to do and it works really well. Plus, kids get to play around with the sudsy water at the end.
(Posted on January 11, 2010)
- doing it today semptember 6 2011 Review by amaris
this was really awesome i mean it is awesome it is better when you have a big soda bottle
(Posted on September 6, 2011)
- great experiment!! Review by jerianne
I did it with 3% too, not as great as a reaction, but still good enuf!! Thanx!!!
(Posted on November 2, 2011)
- WOW!! Review by Kikikomo Hikirombo
this is an expirement that id did as a kid.
(Posted on October 15, 2009)
- The children in my pre-primary class loved the experiment! Review by Mindy
I teach children ages 3-6. The children loved this experiment so much that they asked me to give them a copy of it so they could do it again at home with their parents! I sent all the parents a link to the experiment on Steve Spangler's website. Thanks Steve for another GREAT experiment! I've proudly got a reputation at school as the mad scientist teacher and I owe it all to you! (smile)
(Posted on February 28, 2013)
- Great! Review by Liam
Worked well with 6%!
(Posted on February 20, 2012)