Elephant toothpaste: Fun experiment for kids

As the ingredients react together, you will see lots of bubbles and foam shoot outwards from a plastic bottle. The reaction is caused by hydrogen peroxide coming into contact with yeast. When this happens, it starts breaking down into water and oxygen. As oxygen is a gas, it is trying to escape the liquid. However, the dish soap that is added to the experiment will trap the gas bubbles which will form a foam.

Below, we explain how to make elephant toothpaste, including the materials you need, an easy step-by-step guide, plus some cleanup and safety tips too. The experiment is perfect for kids as it combines fun and education, but just make sure that there is adult supervision throughout and the right safety precautions are in place.

Materials needed

• Gloves and safety goggles
• Clean and dry 500ml plastic bottle
• Bowl
• Funnel
• 125ml 3% hydrogen peroxide
• A small amount of washing-up liquid
• Food colouring
• 2 tbsp warm water
• 1 tsp fast-action yeast
• Small jug

Preparation work

To prepare for your experiment, you should first put your safety goggles and rubber gloves on to protect your skin and eyes from the hydrogen peroxide.

Then clean and dry your 500ml plastic bottle if not done so already and place it into a non-reactive bowl (or oven dish).

We would also suggest that you complete this experiment outside in a garden, or in a large open area as the experiment can yield surprisingly large results! We would also recommend putting an old sheet or piece of tarpaulin down underneath the bowl, this will make it easier to clean up the foam.

Step by step instructions

1. Put a funnel in the top of the bottle, then slowly and carefully pour in the hydrogen peroxide (we would recommend an adult do this part)
2. Remove the funnel straight into a sink or bowl (make sure you don't drip any hydrogen peroxide that might still be in it)
3. Add a squirt of washing-up liquid to the bottle
4. Add a few drops of food colouring to the bottle, then gently shake the bottle to mix the ingredients together (make sure to keep the bottle upright)
5. Stir the yeast and warm water together in a small jug
6. To do the experiment, pour the yeast mixture into the bottle and move away quickly
7. Watch as the mixtures react together and burst out of the bottle

Cleaning up after the experiment

When you are done with the experiment, it is safe to wash the foam down the sink or drain. If you get any of the foam or 'toothpaste' on your clothes or skin, rinse immediately with soap and water. The bottle, funnel and other equipment used can be cleaned with warm, soapy water.

Safety tips

The hydrogen peroxide used can can be dangerous if swallowed and can also cause skin irritation. Gloves and safety goggles should be worn throughout by anyone taking part in the experiment. And if you have a lab coat or apron, you might want to wear that too. We would also recommend that adults carefully pour the hydrogen peroxide into the funnel at the start of the experiment.

When the experiment takes place, the foam will shoot up very high out of the bottle, so make sure you move away quickly once you start the chemical reaction. Doing the experiment in a large tray or tub, or outside, will make it much easier to clean up all of the foam.

The foam released in the reaction will also be hot — so do not touch it right away, wait a few minutes until it's cool and then only touch the foam whilst wearing gloves. The foam and equipment may still contain some unreacted hydrogen peroxide, so do be careful when cleaning up. As mentioned above, if the foam or any hydrogen peroxide touches skin, immediately wash it with soap and water.

Pic: Getty

Credit: Science Buddies

Read more:

• Easy science experiments for kids
• How to make slime
• Make your own bubble solution
• Easy homemade playdough recipe
• How to make a paper airplane