What is an elephant’s toothpaste reaction and why has it fascinated chemists for so long? Time to find out.
What you need:
Hydrogen peroxide (available in the cleaning section of a supermarket near you or at a beauty parlour, the strength should be 6%)
A packet of dry yeast
Warm water
A tablespoon
Liquid dish soap
A one-litre plastic bottle
A small cup Food colouring (optional)
A plastic sheet
Adult supervision
What to do:
1. Spread the plastic sheet on a table. Place the plastic bottle on the sheet.
2. Pour half a cup of the hydrogen peroxide into the plastic bottle (at least 2 inches).
3. Add 8-10 drops of food colouring.
4. Add one tablespoon of the liquid dish soap into the bottle. Swirl the bottle to let the liquids mix.
5. Now, in a separate cup, mix one tablespoon of the yeast with three tablespoons of warm water. Let them mix for about 30 seconds.
6. Pour the yeast mix into the bottle and step away quickly!
What happens:
The mixture bubbles and spits out a column of foam! No wonder most people like to call this foaming reaction an elephant’s toothpaste-this is how toothpaste may look after an elephant spits it out. Heh
Why?
The chemical formula for hydrogen peroxide is H202, which means it is made up of hydrogen (H) and oxygen (0) atoms. The yeast acts as a catalyst (a helping chemical) that removes one oxygen atom from the peroxide, thereby splitting it into water (whose chemical formula is H20) and oxygen. The speed of the reaction creates bubbles that are full of this oxygen (the soap helps the foaming too). So the foam basically contains water, oxygen and soap. If you touch the bottle, you find that it is warm to the touch. This means that this reaction has produced heat as a byproduct.
Such reactions that produce heat are known as ‘exothermic reactions’ where ‘exo’ means ‘outwards and ‘thermic’ points to thermal energy or heat.
Picture Credit : Google
