Percent Yield Calculator Formula

Understand the math behind the percent yield calculator. Each variable explained with a worked example.

Use the Percent Yield Calculator

Formulas Used

Percent Yield

pct_yield = (actual_yield / theoretical_yield) * 100

Product Lost

loss = theoretical_yield - actual_yield

Variables

VariableDescriptionDefault
actual_yieldActual Yield(g)3.5
theoretical_yieldTheoretical Yield(g)5

How It Works

Percent Yield

Percent yield measures how efficient a chemical reaction is by comparing the actual product obtained to the maximum amount theoretically possible.

Formula

% Yield = (Actual Yield / Theoretical Yield) × 100

Theoretical yield is calculated from stoichiometry using the limiting reagent. Percent yields below 100% are caused by incomplete reactions, side reactions, and losses during purification.

Worked Example

A synthesis produces 3.5 g of product from a theoretical maximum of 5.0 g.

actual_yield = 3.5theoretical_yield = 5
  1. 01% Yield = (3.5 / 5.0) × 100 = 70.00%
  2. 02Product lost = 5.0 - 3.5 = 1.5 g

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Open Percent Yield Calculator