\Elephant toothpaste\ demonstration. This reaction produces prodigious amounts of foam due to the rapid decomposition of hydrogen peroxide into water and oxygen. In this reaction, hydrogen peroxide solution (35%, 100mL) is added to a one-litre measuring cylinder. A small amount of liquid detergent is added, which traps the oxygen gas produced. Red food dye is also added, for show. Lastly, a catalyst (solid potassium iodide) is added to the reaction vessel. This greatly speeds the reaction, by providing a more favourable energy pathway.