Q: What is the term for a substance that increases the rate of a chemical reaction but is not changed or used up in the reaction?


Read this paragraph and choose the correct option from the provided answers:

Some reactions need extra help to occur quickly. They need another substance, called a catalyst. A catalyst is a substance that increases the rate of a chemical reaction but is not changed or used up in the reaction. The catalyst can go on to catalyze many more reactions.

 Choices:

- a mechanism

- an acid

- a contribute

- a catalyst


A:
a catalyst