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Science

What is A catalyst?

A catalyst is a substance that speeds up a chemical reaction without being used up itself. It gives the reaction an easier path, so it happens faster or at a lower temperature — then the catalyst comes out unchanged, ready to work again. Enzymes in your body are natural catalysts.

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Key things to understand

  • 1Speeds up a reaction without being consumed.
  • 2Gives the reaction an easier, lower-energy path.
  • 3Comes out unchanged and reusable.
  • 4Enzymes are the body's natural catalysts.

Frequently asked questions

How does a catalyst speed up a reaction?
It lowers the activation energy — the 'hill' a reaction must climb — so more molecules can react, faster.
Is a catalyst used up in the reaction?
No — it takes part but is regenerated by the end, so a small amount works over and over.
What are everyday examples of catalysts?
A car's catalytic converter, enzymes in digestion, and yeast in baking all act as catalysts.

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