Answer: The substances present at the start of the reaction are "reactants" and the substances produced are "products"
Step-by-step explanation:
When a reaction happens between different substances, it will produce a product or some products. The best way to visualize this process is using a chemical reaction, where the substances that are reacting will be on the left side and they will be called reactants and the substances produced will be on the right side of the equation and they will be called products. As we can check in the image.