Hrithvik's Journal - Elephant toothpaste

Elephant toothpaste is a fun and exciting chemistry experiment that produces a massive foamy eruption. This reaction demonstrates the rapid decomposition of hydrogen peroxide into water and oxygen, accelerated by a catalyst. In this guide, we will use potassium iodide (KI) as the catalyst along with soap oil solution to trap the oxygen and create a dramatic foam explosion.

Materials Needed:

• 100 mL of 30% hydrogen peroxide (H2O2)
• 5 g of potassium iodide (KI)
• 10 mL of liquid dish soap (soap oil solution)
• 100 mL graduated cylinder or a tall container
• Safety goggles and gloves
• Stirring rod
• Tray or plastic sheet to catch the foam
• Food coloring (optional, for visual effect)

Safety Precautions:

• Wear gloves and safety goggles at all times.
• Use hydrogen peroxide with caution, as high concentrations can cause burns.
• Perform this experiment in a well-ventilated area.
• Do not touch the foam immediately, as the reaction generates heat.

Procedure:

Step 1: Prepare the Container
Place your graduated cylinder or tall container on a tray or plastic sheet to catch the foam overflow. If you want to add color to the foam, put a few drops of food coloring into the container.

Step 2: Add Soap Solution
Pour 10 mL of liquid dish soap into the container. Gently swirl the container to mix the soap with the hydrogen peroxide, ensuring that it will trap the oxygen gas effectively.

Step 3: Add Hydrogen Peroxide
Carefully pour 100 mL of 30% hydrogen peroxide into the container. Be cautious while handling it, as it is a strong oxidizer.

Step 4: Introduce the Catalyst
In a separate small beaker, dissolve 5 g of potassium iodide (KI) in a small amount of water to form a solution. Quickly pour the KI solution into the container and step back.

Step 5: Observe the Reaction
Almost instantly, a thick, voluminous foam will shoot up and overflow from the container. This happens because potassium iodide catalyzes the decomposition of hydrogen peroxide into water and oxygen gas:
2H2O2 ? 2H2O + O2 (gas)
The soap traps the oxygen gas, creating a huge foam eruption. This reaction is also exothermic, meaning it releases heat, so the foam may feel warm.

Explanation of the Reaction:

Hydrogen peroxide decomposes naturally over time, but potassium iodide significantly speeds up this process by acting as a catalyst. The released oxygen gas gets trapped in the soap solution, creating bubbles and forming a large amount of foam, mimicking toothpaste squeezing out of a giant tube—hence the name "elephant toothpaste."

Conclusion:

This experiment is a fantastic way to visualize chemical reactions, catalysis, and gas production. While it's safe when done correctly, always follow safety precautions to ensure a fun and hazard-free experience. Try different variations, such as using different soap types or adding multiple colors, to make your experiment even more exciting!