What are reactants in a chemical reaction?

What are reactants in a chemical reaction?

• A. Substances that go into a reaction.
• B. Substances that come out of a reaction.
• C. Energy produced by the reaction.
• D. The catalyst.

Answer: (A)

Reactants are the substances that go into a chemical reaction. They are the starting materials you begin with, and in a chemical equation they’re placed on the left side. During the reaction, the bonds in the reactants break and new bonds form to make the products on the right side. The amount of reactants available determines how much product can be produced. Energy involved in a reaction isn’t a substance, so it isn’t a reactant, even though heat or light can drive a reaction. A catalyst speeds up the reaction without being consumed, so it’s not considered a reactant either.

Reactants are the substances that go into a chemical reaction. They are the starting materials you begin with, and in a chemical equation they’re placed on the left side. During the reaction, the bonds in the reactants break and new bonds form to make the products on the right side. The amount of reactants available determines how much product can be produced.

Energy involved in a reaction isn’t a substance, so it isn’t a reactant, even though heat or light can drive a reaction. A catalyst speeds up the reaction without being consumed, so it’s not considered a reactant either.