ABSTRACT
The design problem is to identify the reactants and products of a reaction and then to calculate their masses. Stoichiometry is the science of deciphering the qualitative and quantitative information that is given by a balanced stoichiometric equation. A balanced stoichiometric equation shows the chemical composition of the reactants and products and the molar proportions in which they react. Each atom of the elements that make up the reactants must appear on the products side of the equation. The total mass of the reactants must equal the total mass of the products. The masses of the compounds are calculated using the molar masses. A molecule is formed when two or more atoms chemically join together. If the atoms are different from each other, a compound is formed. Not all molecules are compounds, since some, such as hydrogen gas or ozone, consist only of one element or type of atom.
