Reactants

Definition

Reactants are the starting substances that undergo chemical changes in a reaction. They are present before the reaction begins and are transformed into products.

5 Must Know Facts For Your Next Test

1. Reactants are consumed during a chemical reaction.
2. The amount of reactants determines the quantity of products formed.
3. Reactants can be elements, compounds, or molecules.
4. In a balanced chemical equation, reactants are listed on the left side.
5. The rate at which reactants are used up can affect the speed of the reaction.

Review Questions

Related terms

Products: Substances formed as a result of a chemical reaction.

Catalyst: A substance that speeds up a chemical reaction without being consumed.

Activation Energy: The minimum energy required for a chemical reaction to occur.