Elephant Toothpaste Foam Reaction

Easy

A simple mix of hydrogen peroxide and yeast can send a giant column of foam shooting out of a bottle. The reaction happens fast and produces heat you can feel through the bottle. Add hydrogen peroxide and dish soap to a plastic bottle. Drop in some food coloring. In a small cup, mix dry yeast with warm water. Pour the yeast mixture into the bottle and swirl gently. Foam erupts from the bottle almost right away. This is an exothermic reaction (one that gives off heat). Touch the bottle with gloved hands to feel the warmth.

Hypothesis

The hypothesis is that by mixing hydrogen peroxide, yeast, and dish soap together, a reaction will occur that produces a lot of foam.

Science Concepts Learned

Catalysis

Catalysis means a substance helps a reaction happen faster but stays unchanged itself. In this experiment, yeast mixed with warm water is added to hydrogen peroxide. The hydrogen peroxide breaks apart so quickly that a giant column of foam shoots out of the bottle.

Exothermic Reactions

Some chemical changes give off heat as they happen. When yeast meets hydrogen peroxide, the mix breaks apart fast — and you can feel the warmth through the bottle as foam shoots out. That heat is the giveaway: this is an exothermic reaction, one that releases energy as it goes.

Method & Materials

You will mix hydrogen peroxide, dish soap, and food coloring in a bottle, then add yeast mixed with warm water to the bottle. This will cause the foam to overflow out of the bottle!

You will need a clean 16-oz plastic soda bottle, hydrogen peroxide, yeast, dishwashing soap, food coloring, warm water, gloves, safety goggles, and a tray or washable surface to do this experiment on.

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Results

This experiment showed that mixing the hydrogen peroxide, yeast and dish soap together can cause a fun and exciting reaction. The ingredients by themselves don't create large amounts of foam, but only when they're mixed together. The heat is generated because of an exothermic reaction, which is caused by the catalase enzyme in yeast breaking down the hydrogen peroxide into oxygen and water. The foam is caused by the soap trapping the oxygen gas.

Why do this project?

The Elephant Toothpaste experiment is not only visually impressive but also a great way to explore chemistry. With simple ingredients, you can witness a powerful chemical reaction that teaches you about catalysts and exothermic reactions.

Also Consider

Use different colors of food coloring to see how they mix and create new colors in the foam. Vary the amount of hydrogen peroxide and yeast to see how it affects the size and duration of the foam eruption. Use different types of soap and detergents to see if they affect the foam's texture. Use bottles with different-sized openings to create even more gigantic 'Dinosaur Toothpaste' eruptions or tiny 'Mouse Toothpaste' eruptions!