Today’s science fun project was making elephant toothpaste. I wanted to try this experiment but didn’t have everything on hand. I didn’t want to make a special trip to the store just for 6% Hydrogen Peroxide so we made do with 3%.
I started with a 2 liter bottle from our recycling. As I’ve read that it’s very messy I grabbed our red sensory tub. I pulled together my kiddos and the ingredients and took them out to the back yard.
In the bottle we put 1 cup of 3% Hydrogen Peroxide and a few squirts of blue Dawn dish soap. We gently swirled these together and then put the funnel in.
In the measuring cup we added 8 tablespoons of warm water and 2 tablespoons dry active yeast.
Now as this is a chemical reaction it’s important to keep your kids safe. Chemical reactions either create heat or cold and this one can get quite hot. With that in mind it is important to have close adult supervision.
Straight away we learned that there are indeed problems with using the 3% Hydrogen Peroxide. The first was the slow creep up the inside of the bottle instead of the sudden rush of foam bubbles. Second thing we noticed was that it just kind of poured lazily out of the bottle. The chemical reaction is just not as intense. The bottle was warm which means an exothermic reaction took place and the whole thing was like a luke-warm bubbly mess.
I was expecting the kids to be a bit disappointed but kids surprise me almost daily. I asked Izzy what she thought of it and she replied, “pretty neat”. Our two boy guests (14 and 11) showed little interest but they’ve showed little interest in most activities that don’t include video games or food. Our girl guest (17) sat and played with the foam for quite awhile with Izzy.
I knew that main part of the lazy toothpaste was the strength of peroxide but I wondered if a smaller bottle would help. I quickly mixed up another batch and we added it to our bin. Same results – lazy toothpaste.
How it works?
Hydrogen peroxide is first mixed with liquid soap. Then a catalyst, dry bread yeast, is added to make the hydrogen peroxide decompose very quickly. Hydrogen peroxide breaks down into oxygen and water. As a small amount of hydrogen peroxide generates a large volume of oxygen, the oxygen quickly pushes out of the container. The soapy water traps the oxygen, creating bubbles, and turns into foam. Often some food coloring is also added before the catalyst
All over the net you’ll find elephant toothpaste experiments including some pretty neat videos. I personally liked the article at http://www.coolscience.org/CoolScience/KidScientists/h2o2.htm as it straight forward and easy to understand.
My go-to blog for fun and amazing kids activities: Fun at Home with Kids – http://www.funathomewithkids.com/2013/08/fun-science-experiment-for-kids.html has a great set of pictures showing this fun science experiment!
Please note: while the final product after reaction is just soap and water the reaction process can be hot and Hydrogen Peroxide can burn – especially if you have cuts/ scratches on your hands.
Enjoy and if you like what you find here please share with your friends!