Catalysts

Imagine having to climb a high mountain to school every day, and then someone builds you a tunnel straight through it. The way suddenly gets much easier, and the tunnel simply stays there for tomorrow. Chemistry has exactly this kind of helper: the catalyst. Here you'll see what it does.

The hill gets smaller

From activation energy you know the energy hill a reaction has to get over. A catalyst lowers this hill: the reaction needs less of a push and therefore runs faster. The special part is that the catalyst is not used up in the process. At the end it is still exactly there and can support the next reaction straight away. It takes part without being changed itself.

Catalysts in everyday life

The exhaust pipe of every petrol and diesel car holds a catalyst. It turns toxic exhaust gases into less harmful substances without being used up, and it often works for many years. Your body is full of catalysts too: enzymes are bio-catalysts. When you digest, they break your food into tiny building blocks far faster than it would happen on its own. Without enzymes you would wait years for a meal to digest.

Good for industry and the environment

Because catalysts let reactions run at lower temperatures, industry saves a lot of energy with them. One and the same catalyst can convert huge amounts of a substance, because it is left unchanged after every single reaction. That makes producing fertiliser, plastics or medicines cheaper and at the same time protects the environment, because less fuel is needed and less waste is created.