This document discusses stoichiometric calculations and concepts like limiting reactants, theoretical yield, and percent yield. It explains that the coefficients in a balanced chemical equation give the ratio of moles of reactants and products. It also describes how to use the molar ratios to calculate the mass of a product formed or reactant used from the mass of another substance. Sample stoichiometry problems are provided that involve calculating moles or masses of substances. The concepts of limiting reactant, theoretical yield, and percent yield are defined.