Mariajose Bravo #6Mariajose Quintanilla #21

Alejandra Lozano #17Valeria Lopez #16

Daniela Hernandez #14

Chemical Reaction

Oxygen quickly leaves the system

causing strong foaming of the

detergent, so the foam erupts out.

Steam rising from the foam shows that

the reaction is exothermic (gives off

heat). Minimum quantities of iodine

are being liberated and can be

detected by its colour if the experiment

is done without dyes.

The iodide ions from potassium iodide

acts as a catalyst—it speeds up the

reaction without being consumed in the

reaction process. The iodide ion

changes the mechanism, by which the

reaction occurs

Elephant Toothpaste

Liceo De Monterrey

Science Fair

7C

SCIENCE FAIR

ELEPHANT TOOTH-PASTE

What is Elephant Toothpaste?

Elephant toothpaste is a foamy substance caused by the rapid decomposition of hydrogen peroxide. This is often used for classroom demonstrations because it requires only a small amount of ingredients and makes a "volcano of foam". This is also known as the "Marshmallow Experiment" in some cases.

Material

Hydrogen peroxide (30%) - This is ten times stronger than the normal hydrogen peroxide you can find at the store

Sodium iodide solution, 2 Mor

Potassium iodide solution, 2 M

Liquid soap Food coloring Graduated cylinder (500

mL) Safety glasses Rubber gloves for clean-up

Procedure

1. The first step is to put on your safety glasses.

2. Measure 20 mL of the 30% hydrogen peroxide into the graduated cylinder. It's best to place the cylinder in a large tray to make the clean-up as easy as possible.

3. Add a squirt (that's a technical term meaning about 5 mL) of dish soap to the graduated cylinder containing the 30% hydrogen peroxide.

4. Add a few drops of food coloring to spice things up.

5. The last step is to add 5 mL of the 2M sodium iodide solution (2M refers to the molarity of the solution). The reaction

takes place quickly, so it's important to stand back.

6. You'll notice that the foam has a brown tint. This is due to the

presence of free iodine produced by the extreme oxidizing power of the 30% hydrogen peroxide.

Caption describing picture or graphic.

1. Wear safety goggles. Also, wear disposable gloves when pouring 30% hydrogen peroxide, as it is a very strong oxidant. 2. Do not stand over the graduated cylinder because steam and oxygen are produced quickly.