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Hey, reader! Welcome to yet another chemistry post. Today’s topic is the famous elephant’s toothpaste experiment and the chemistry behind it. With that said, let’s begin!

Instructions – Home Version

Materials:

• Conical flask
• Beaker
• Hydrogen Peroxide >10%
• Soap
• Baking Yeast
• Hot water
• Food coloring (Optional)

Procedure:

1. Add hot water to the conical flask.
2. Dissolve the yeast in the water by spinning the flask.
3. Add dish soap.
4. If you choose to, add food dye.
5. Add the peroxide to a beaker.
6. Standing back, add the peroxide to the flask and watch the eruption!

Warning: the reaction is exothermic, and so the foam will be hot. Always remember to wear protective gloves as hydrogen peroxide is corrosive.

Instructions – Lab Version

Materials:

• Conical flask
• Beaker
• Hydrogen Peroxide 30%
• Dish soap
• Potassium Iodide (KI)
• Food coloring (Optional)

Procedure:

1. Add KI to the flask.
2. Mix it with dish soap.
3. In a beaker, add H₂0₂ (Hydrogen Peroxide)
4. Standing back and prepared to move away, pour the contents of the beaker into the flask

Warning: the reaction will be much more aggressive than the home version and will even shoot up. Pour the peroxide standing away and never look at it pour from the top, unless you want a nice splash of boiling potassium iodide in your face.

Chemistry behind the Experiment

Hydrogen Peroxide differs from water by 1 extra oxygen atom. However, the force holding it is pretty weak, and so it will slowly decompose even without external factors into oxygen and water:

However, the rate at which its happening is pretty slow and only noticeable by adding extra heat (like boiling it) or using a catalyst (a substance that speeds up a reaction).

Baking yeast contains a substance called catalase, which can catalyze the reaction. This is why adding it to the peroxide creates bubbles. Another catalyst is Potassium Iodide (KI). It speeds up the reaction to the point where the foam shoots up into the air.

Ok, we figured out the main idea behind it, but don’t the bubbles just pop? Well, this is the exact reason soap is added to the catalyst. When oxygen is released, the soap traps it creating foam. As more foam is created, it is forced up the opening of the flask and an eruption is created.

Guinness World Record

The experiment was found to be fascinating by many people and some decided to take it up a notch. On April 22, 2022, KiwiCo beat the Guinness World Record for the largest elephant toothpaste eruption, with over 300 cm³ of foam created.