A catalyst increases the rate of a reaction. What does it do?
Answer and explanation
Correct answer: A. It provides an alternative route with a lower activation energy
- Step 1: A catalyst lowers the activation energy by offering a different pathway.
- Step 2: More collisions then have enough energy to react, and the catalyst is unchanged at the end.
Answer
It provides an alternative route with a lower activation energy.
Why not the others: It increases the energy released by the reaction: a catalyst does not change the enthalpy change. It is used up and so shifts the products formed: a catalyst is not used up. It raises the temperature of the reaction mixture: a catalyst does not heat the mixture.
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