Final answer:
Chemical reactions involve the formation of substances known as products, which are formed from the reactants. Reactants and products are the key substances involved in a chemical reaction, and the total mass of the reactants is conserved in the reaction.
Step-by-step explanation:
Chemical Reactions and Substances
Chemical reactions occur when reactants combine or transform to form products. In a chemical reaction, atoms rearrange to form new substances with different properties. Reactants are the substances present at the beginning of a chemical reaction, while products are the substances formed as a result of the reaction. The mass of the reactants is conserved in a chemical reaction, meaning that the total mass of the reactants is equal to the total mass of the products.
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