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Single-limiting-reactant yield

Percent yield from reactant grams

If you know which reactant limits the reaction and have its mass, the balanced equation gives a theoretical product amount. Compare that mass with the product actually recovered to calculate percent yield.

Enter your values

Result

Results are based only on the inputs and assumptions shown here. Nothing you enter is sent or saved.

Formula: theoretical product g = (reactant g ÷ reactant g/mol) × (product coefficient ÷ reactant coefficient) × product g/mol; percent yield = actual product g ÷ theoretical product g × 100

Worked example

Ten grams of a 50 g/mol limiting reactant is 0.2 mol. A balanced reaction with 2 reactant units yielding 1 product unit gives 0.1 mol product, or 10 g at 100 g/mol. If 8 g is isolated, percent yield is 80%.

Identify the limiting reactant first

This page assumes the entered reactant is truly limiting and every other required reactant is available in excess. It does not balance the equation or determine a limiting species from several quantities; use the separate limiting-reactant tool if that is unknown.

Coefficients come from one balanced equation

Enter the whole-number coefficients of the chosen reactant and product in the same balanced reaction. OpenStax defines theoretical yield from reaction stoichiometry and percent yield from actual divided by theoretical product.

More than 100% is a measurement warning

If actual mass exceeds the theoretical result, the calculator shows the number and flags it for review. Product moisture, impurities, incorrect molar masses, wrong stoichiometry or an incorrectly identified limiting reactant can explain a mismatch. A high value is not evidence that a reaction exceeded the stoichiometric maximum.

Explore the related calculation

For a different starting point, try the limiting reactant calculator or return to the main calculator. Browse the complete tool directory for this site.

Reference and corrections

The definitions and assumptions above follow these sources; the examples and calculator arithmetic are original to this page.

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