Module 7: Stoichiometry

You have learned that by using precise measurements and accurate calculations, you can measure the amount of products that are created by specific reactants. This branch of chemistry, known as stoichiometry, began even before people understood what an atom was. Between 1792 and 1794 Jeremias Benjamin Richter published a three-volume summary of his work on the Law of Definite Proportions. In this book Richter introduced the term stoichiometry, which he defined as the "art of chemical measurements, which has to deal with the laws according to which substances unite to form chemical compounds."

As you have learned in this module, stoichiometry is not only used in the field of chemistry. Stoichiometry helped to save the lives of astronauts during the Apollo space missions. Stoichiometry is important in the study of ecology. Using the principles of stoichiometry, ecologists can study and understand the balance of energy, elements, and organisms in certain ecosystems. Other aspects of stoichiometry, like percent yield, help engineers study the efficiency of processes.