Segment #3 - Elephant Toothpaste

Elephant Toothpaste

Segment 3

Welcome to the Science Playground! Today we're going to be exploring ELEPHANT TOOTHPASTE!

The ingredients you're going to need for this experiment include:

• 3% Hydrogen Peroxide
• Dry Pure Yeast
• Dawn Dish Soap
• Food Colouring (Optional)

The materials you're going to need for this experiment includes:

• A Beaker or 2L Pop Bottle
• Funnel
• Bowl
• A Pan (Optional - prevents messes!)
• Measuring Cups
• Mixing Utensils

For this experiment, we recommend that you use gloves, goggles, and an apron or lab coat to protect yourself from spills or splashes. Please keep in mind that this reaction is reaction is exothermic, so it does produce a little bit of heat.

The first step in our experiment is to prep the dry yeast. You must take your bowl and dissolve the yeast in some warm water. We're going to take one teaspoon of our dry yeast and place it in our bowl. We're then going to take two tablespoons of warm water. From there, you're going to mix the yeast and water until it has fully dissolved. 

While our yeast is activating, place your bottle or beaker in the centre of your tray. Add 1/2 cup of hydrogen peroxide to your container/beaker, then add a few drops of food colouring. Lastly, add a few drops of dish soap to your mixture. Use a spoon to mix it all together.

The final step in our experiment is to add our activated yeast to our coloured hydrogen peroxide solution of 3%. As you can see, when we mix our hydrogen peroxide solution to our yeast, a steady production of hot foam is produced. If we are to do this experiment a concentrated hydrogen peroxide solution greater than 3%, the hot foam will expand the same way, however this time it will expand much faster.

Lets take a look at this experiment a little closer. A hydrogen peroxide molecule consists of two hydrogen and two oxygen molecules. The solution you buy in stores also contain lots of water molecules. The higher the concentration listed on the bottle, the more hydrogen perxoide molecules and the fewer water molecules it will contain. Hydrogen peroxide is a relatively unstable compound and it breaks down on its own into water and oxygen, given a little bit of time. The catalyst in our experiment, known as catalase, is produced by the yeast.

In this reaction, the catalase in the yeast rapidly breaks the bonds of the hydrogen peroxide molecules. The H2O2 molecule loses one oxygen molecule. Since oxygen molecules do not like to be by themselves, they attach together, create O2, and float out of the solution. When the bonds of a molecule are broken in this fashion, energy is released - usually in the form of heat. Usually if the bonds break on their own over time, only a small increase in temperature can be noticed. Since we used the catalyst in this experiment to increase the rate that the hydrogen peroxide breaks down, we also increase the rate at which energy is released. The rapid release of energy causes a dramatic increase in our temperature of our solution, making it exothermic. The large number of escaping oxygen bubbles become trapped in the dish soap molecules, producing large amounts of hot foam, also known as elephant toothpaste.

So that's it for today guys! I hope you all enjoyed today's experiment, stay tuned for our next segment on INSTANT WATERBENDING!

 If you have any questions regarding this experiment or science in general, feel free to email me at englishprojectscience@gmail.com