yield

chemistry

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June 29, 2026

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In chemistry, yield refers to the amount of product obtained from a chemical reaction. It's a crucial factor in evaluating a synthetic method, indicating how efficiently reactants are converted into the desired product.1

A low yield can occur if a reactant forms an alternative product, if the product reacts further, or due to losses during isolation. The yield is typically expressed as a percentage, representing the actual amount of product obtained compared to the theoretical maximum. For instance, a yield of 80 percent means 80 out of a possible 100 molecules were formed.1

The ultimate goal in ideal synthesis is 100 percent "atom efficiency," where all atoms from the reagents are incorporated into the final product without by-products. Yield directly impacts the cost of a product and can determine the feasibility of a synthesis, as the overall yield is the product of individual step yields.1

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chemical compound
Evaluation of a synthetic method
Second, the yield in each step must be considered. A step in a synthesis may give a very low yield of the desired product. For example, a proportion of the reactant may be converted into a different product by an alternative process that competes with the desired…
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Second, the yield in each step must be considered. A step in a synthesis may give a very low yield of the desired product. For example, a proportion of the reactant may be converted into a different product by an alternative process that competes with the desired…
Read More

green chemistry
Atom economy
…the traditional concept of “yield,” the amount of final products, which was used for calculating the efficiency of chemical reactions. To calculate the yield, chemists traditionally considered only the amount of the main chemical product they intended to produce (“target molecules”) and not by-products, which might include environmentally hazardous…
Read More
…the traditional concept of “yield,” the amount of final products, which was used for calculating the efficiency of chemical reactions. To calculate the yield, chemists traditionally considered only the amount of the main chemical product they intended to produce (“target molecules”) and not by-products, which might include environmentally hazardous…
Read More