Colored Foamy Fountain (Elephant Toothpaste)

Want to make bursting colorful foam? Here is how you do it, using only materials you can find at home. It is easy and fun, and it's called Elephant Toothpaste.

You'll need these materials: Safety goggles; 16 oz. empty plastic bottle; 0.5 cup of hydrogen peroxide (6% or "20-volume" is good and can be obtained at a pharmacy or salon); 1 tbsp. dry yeast; 3 tbsp. warm water; 1 tbsp. dishwashing soap; 8 drops of food coloring (be creative with colors!); a small cup for mixing water and yeast; a small funnel.

Get prepared: Use safety googles to protect your eyes. Make sure to do the experiment on a surface or in a tray that can be easily cleaned. You are going to make a lot of foam!

Here's what you do: Use the funnel to add 0.5 cup of hydrogen peroxide into the empty bottle. Next, add 1 tbsp. of dishwashing detergent and 8 drops of food coloring (any colors). Swirl to mix. In a separate cup, mix thoroughly 3 tbsp. of warm water with 1 tbsp. of yeast. When you are ready, use the funnel to quickly add the yeast solution to the hydrogen peroxide solution. Stand back and watch!

What's happening? Hydrogen peroxide is H2O2, which means it is water (H2O) with one extra oxygen. When yeast is added, it acts as a catalyst to split the hydrogen peroxide into water and oxygen. Bubbles of oxygen are trapped in the soap, which transforms into the foam fountain we observe. This experiment is an exothermic reaction; it releases heat. The bottle is warm to the touch after the experiment is over.

This is a great high school level at-home experiment, but remember, it is messy! Thanks to Nour Hussein of U.T. Arlington for submitting this to DISCUS. She acknowledged http://www.sciencebob.com/ and http://www.youtube.com/ for information on how to set up and perform this great activity.