Percent yield

Science

Definition

Percent yield measures the efficiency of a chemical reaction by comparing the actual yield (what you obtained) to the theoretical yield (the maximum possible based on stoichiometry). Reactions rarely achieve 100% yield due to side reactions, incomplete reactions, or loss during purification.

Examples

  • A reaction with a theoretical yield of 10 g producing only 8 g gives 80% yield
  • Pharmaceutical synthesis aiming for high percent yield to reduce waste
  • Industrial Haber process optimizing conditions to maximize ammonia yield
Key Fact

% Yield = (actual yield / theoretical yield) × 100%.

Related Terms

Stoichiometry Limiting reagents Molar ratios Reaction rates

Study This Concept

Practice percent yield with free review games in these units:

Chemistry Unit 5: Stoichiometry