Elephant Toothpaste???

What do you get when you put elephants and toothpaste together???

How's producing so much toothpaste even possible??

This probably comes to you as a surprise as steaming foam will look to you like toothpaste, in the amount that an elephant might use. So, buckle up and get ready to learn and experience chemistry in a different level!

To start off, you will need:

• 50-100ml of 30% hydrogen peroxide (H₂0_{2) solution}
• _{Staturated potassium iodide (KI) solution}
• _{Liquid dishwashing detergent}
• Food colouring
• 500ml graduated cylinder
• Splint (optional)

Before beginning the experiment and for safety purposes, wear disposable gloves and safety glasses. Oxygen is evolved in this reaction, so do not perform this demonstration near an open flame. Also, do not lean over the graduated cylinder when the solutions are mixed as the reaction is exothermic(in other words, heat is released)!


To begin,

1.        Put on gloves and safety glasses. The iodine from the reaction may stain surfaces so you might want to cover your workspace with an open garbage bag or a layer of paper towels.

2.        Pour roughly 50 mL of 30% hydrogen peroxide solution into the graduated cylinder.

3.        Squirt in a little dishwashing detergent and swirl it around.

4.        You can place 5-10 drops of food coloring along the wall of the cylinder to make the foam resemble striped toothpaste.

5.        Add ~10 mL of potassium iodide solution. Do not lean over the cylinder when you do this, as the reaction is very vigorous and you may get splashed or possibly burned by steam.

6.        You may touch a glowing splint to the foam to to relight it, indicating the presence of oxygen.

You will be able to observe this! :)

What actually happens is this:

2 H₂O₂(aq) --> 2 H₂O(l) + O₂(g)

However, the decomposition of the hydrogen peroxide into water and oxygen is catalzyed by the iodide ion.

H₂O₂(aq) + I^-(aq) --> OI^-(aq) + H₂O(l)

H₂O₂(aq) + OI^-(aq) --> I^-(aq) + H₂O(l) + O₂(g)

The dishwashing detergent captures the oxygen as bubbles. Food coloring colours the foam. The heat from this exothermic reaction causes the foam to steam. If the demonstration is performed using a plastic bottle, you can expect slight distortion of the bottle from the heat. What a simple yet interesting experiment! So, remember what you can do when you're on a mission to help brush an elephants teeth! hehehe!