Yield

Yield is the amount of product obtained in a chemical reaction. The absolute yield can be given as the weight in grams or in moles (molar yield). The relative yield, which serves to measure the effectiveness of a synthetic procedure, is calculated by dividing the amount of the obtained product in moles by the theoretical yield in moles.

One or more reactants in a chemical reaction are often used in excess. The theoretical yield is therefore calculated based on the molar amount of the limiting reactant, taking into account the stoichiometry of the reaction. For the calculation it is usually assumed that there is only one reaction involved.