A quick and easy experiment for Easter that gives great results! You don't have to make a bunny - you can make any shape you like.
Adult supervision is required.
Do not eat the borax crystals!
The science behind it:
When the water is hot, more borax can dissolve in it than when it is cold. The water is heated to make sure LOTS of borax dissolves in it, until no more can dissolve. This is called a saturated solution – nothing more can dissolve in it. When the water cools down, the borax crystallizes (it “undissolves”) as less borax dissolves in cold water. The pipe cleaner gives a surface for the crystals to form on.
Why can more borax dissolve in hot water? This involves the particles of water. Water particles are constantly moving past one another. There are tiny gaps between the particles. When borax dissolves in water, it fits in between the particles - in the gaps. Hot water particles move faster around each other as they have more energy. This means that the gaps between them are bigger than when the water is cold. So more borax can fit in between the gaps - more can dissolve in the hot water!
Fizzy drinks are an example of a supersaturated solution. There is an excess of carbon dioxide in the soda. Rainclouds are supersaturated with water – so much so that the water vapour in them condenses and falls as rain.