Elephant Toothpaste

This COOL chemical reaction spews froth and foam everywhere. Just like a gigantic tube of toothpaste fit for an elephant.

Suitable for kids aged 5+ with parental supervision.

You Need:
  • An empty soft drink bottle (600mL size works best)
  • cup of 6% hydrogen peroxide solution (purchased from a hairdresser/beauty supply store or chemist)
  • Squirt of dishwashing liquid
  • 4 drops of food colouring
  • 1 teaspoon of dry bakers yeast dissolved in approximately 2 tablespoons of warm/hot water
  • Funnel
  • Safety goggles
  • Lab smock (optional)
  • Tray or foil cake tin to contain mess (optional)
NOTEThe best part of this chemical reaction is that it makes a BIG mess. We have listed safety goggles, smock, and trays in the equipment section to contain the foaming mess. Avoid getting hydrogen peroxide on the skin and follow all instructions on the container.
What to do:
  1. Put on your smock and safety goggles.
  2. Set out all the chemicals needed for this chemical reaction in front of you tin or tray to contain mess (optional), empty plastic bottle, dishwashing liquid, food colouring, peroxide and dissolved yeast. An organised scientist is a good scientist 
  3. Stand the bottle in the tray if you are using one. Using the funnel, pour the hydrogen peroxide into the bottle and 4 drops of food colouring.
  4. Then add a squirt of detergent to the bottle.
  5. Now for the fun bit! Pour in the yeast mixture and quickly remove the funnel. Wow! Feel the bottle. What has changed during the chemical reaction? The warm foam is safe to play with (its just soap, water and oxygen bubbles).

Why is it so?

Look at that oozing luscious toothpaste foam. What a wonderful chemical reaction! The chemical symbol for hydrogen peroxide is very similar to water except it has 2 oxygen atoms instead of 1. Hydrogen peroxide molecules are very unstable and naturally breakdown into water and oxygen gas. A small amount of heat is also released as it is an exothermic reaction. Yeast is the catalyst in this reaction, and makes the peroxide molecule release its oxygen atom faster. All the fix and foam is caused by the quickly released oxygen gas. The foam is safe to play with - it just contains oxygen bubbles, soap and water. Enjoy!