This lecture covers the algorithm for solving chemical reaction engineering problems, including mole balances, rate laws, stoichiometry, and energy balances. It explains the steps involved in designing reactors for different types of reactions, such as batch, CSTR, PFR, and PBR. The lecture also discusses the concept of conversion with respect to the limiting reagent and the design equations for batch, CSTR, PFR, and PBR reactors. Various case studies and examples are presented to illustrate reactor sizing and conversion calculations.