Question

Catalyst are________ that increase the rate of a chemical reaction.

Answer 1

Answer: A catalyst speeds up a chemical reaction, without being consumed by the reaction. It increases the reaction rate by lowering the activation energy for a reaction.

Step-by-step explanation:

Answer 2

substances

Step-by-step explanation:

I would simply put it as catalysts are substances that increase the rate of a chemical reaction.

Keep in mind there are numerous synonyms for substances such as things etc. which could defintely be applicable as an answer therefore, the answers might vary.