Final answer:
A chemical equation is a concise description of a chemical reaction, representing the reactants and products.
Step-by-step explanation:
A chemical equation is a concise description of a chemical reaction. It represents the reactants, which are the starting materials, and the products, which are the final substances. Chemical equations are written with reactants on the left and products on the right, separated by an arrow. For example, the chemical equation for the synthesis of water is:
2H2 + O2 → 2H2O
This equation represents the reaction where two molecules of hydrogen gas combine with one molecule of oxygen gas to form two molecules of water.