Fraction of the theoretical yield that is actually obtained, usually expressed as a percentage.

• A. Theoretical yield
• B. Actual yield
• C. Yield efficiency
• D. Percent yield

Answer: (D)

The idea being tested is how we measure how well a reaction performs by comparing what actually comes out to what could possibly come out. The fraction of the theoretical yield that is actually obtained, expressed as a percentage, is called percent yield. You first determine the theoretical yield from stoichiometry using the limiting reactant, then measure the actual amount you recovered, and finally compute percent yield as (actual yield ÷ theoretical yield) × 100%. So, percent yield is the standard term for this efficiency measure. Theoretical yield is the maximum possible amount, actual yield is the real amount obtained, and yield efficiency is a related term but not the conventional name for this specific percentage.