Stoichiometry is a mathematical tool that is used to quantify the amounts of substances involved in chemical reactions. It involves balancing chemical equations, which means making sure that the same number of atoms of each element are present on both the reactant and product sides of the equation. Once the chemical equation is balanced, we can use stoichiometry to determine the amount of products that can be formed from a given amount of reactants, or the amount of reactants needed to produce a given amount of product. Stoichiometry is critical in many areas of chemistry, including analytical chemistry, biochemistry, and industrial chemistry.