Elephant toothpaste is a foamy substance caused by the rapid decomposition of hydrogen peroxide when combined with dish soap and potassium iodide solution. This classroom demonstration produces a large amount of foam that "erupts" out of the graduated cylinder used in the reaction. Steam rises from the foam, indicating an exothermic reaction, and a small amount of iodine is released, detectable by its brown color in the foam. The potassium iodide acts as a catalyst to speed up the reaction without being consumed.

1. Elephant
Toothpaste
ELEPHANT
TOOTH- 7C
PASTE
Caption describing picture or graphic.
SCIENCE
FAIR
Oxygen quickly leaves the system
causing strong foaming of the
detergent, so the foam erupts out.
Steam rising from the foam shows that Science Fair
the reaction is exothermic (gives off
heat). Minimum quantities of iodine Mariajose Bravo #6
Mariajose Quintanilla #21
are being liberated and can be
Alejandra Lozano #17
detected by its colour if the experiment Valeria Lopez#16
is done without dyes. Daniela Hernandez #14
The iodide ions from potassium iodide
acts as a catalyst—it speeds up the
Liceo De Monterrey
reaction without being consumed in the
reaction process. The iodide ion
changes the mechanism, by which the
reaction occurs ChemicalReaction

2. Material Procedure
Hydrogen peroxide (30%) 1. The first step is to put on your
- This is ten times stronger safety glasses.
than the normal hydrogen 2. Measure 20 mL of the 30%
peroxide you can find at hydrogen peroxide into the
the store graduated cylinder. It's best to
Sodium iodide solution, 2 place the cylinder in a large
M tray to make the clean-up as
or easy as possible.
What is Elephant Potassium iodide solution, 3. Add a squirt (that's a technical
Toothpaste? 2M
term meaning about 5 mL) of
dish soap to the graduated
Liquid soap
Elephant toothpaste is a foamy cylinder containing the 30%
Food coloring hydrogen peroxide.
substance caused by the rapid
Graduated cylinder (500 4. Add a few drops of food
decomposition of hydrogen mL) coloring to spice things up.
peroxide. This is often used for Safety glasses 5. The last step is to add 5 mL of
classroom demonstrations because Rubber gloves for clean-up the 2M sodium iodide solution
it requires only a small amount of (2M refers to the molarity of
ingredients and makes a "volcano 1. Wear safety goggles. Also, the solution). The reaction
of foam". This is also known as the wear disposable gloves when takes place quickly,so it's
pouring 30% hydrogen peroxide, important to stand back.
"Marshmallow Experiment" in
as it is a very strong oxidant. 6. You'll notice that the foam has
some cases. a brown tint. This is due to the
2. Do not stand over the
graduated cylinder because presence of free iodine
produced by the extreme
steam and oxygen are produced
oxidizing power of the 30%
quickly. hydrogen peroxide.