What does a catalyst do?
Answer and explanation
Correct answer: B. It speeds up a reaction and is not used up
- Step 1: A catalyst provides an alternative pathway with lower activation energy.
- Step 2: It is unchanged at the end of the reaction.
Answer
It speeds up a reaction and is not used up.
Why not the others: It is used up while it speeds up the reaction: catalysts are not consumed. It slows the reaction down: that is an inhibitor. It increases the mass of the products: a catalyst does not change the yield.
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