Limiting Reactant and Yield Calculator
Use an atom-balanced equation and available reactant masses to find the limiting reactant, leftover material and theoretical product masses.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
First balance the equation. Convert each reactant mass to moles and divide by its reaction coefficient. The smallest ratio limits reaction extent. Use that extent to calculate consumed reactants, leftovers and each theoretical product.
Extent=min(available moles/coefficient); product moles=extent×product coefficient
Worked example
For2H2+O2→2H2O,4.032g H2 and31.998g O2 are stoichiometric using the stored weights. They yield36.030g water theoretically and leave no excess reactant.
Assumptions and input details
Masses are nonnegative and listed in reactant order, sharing one selected unit; converted masses are capped at1e12g. Recovery0–100% scales each product’s theoretical mass and is entered by you. The balanced-equation limits and84-element table apply. This is stoichiometric bookkeeping with complete consumption of the limiting reactant; kinetics, side reactions, mixtures and equilibrium are not modeled. Molar masses and numerical ties are approximate; mole calculations extend middle-school mass-ratio work.
References: OpenStax limiting reactants and yields
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
The 19 mass definitions distinguish avoirdupois and troy measures, metric and regional measures. Japanese kin is 600 g; mainland Chinese shijin is 500 g.
Regional measures are not interchangeable merely because their names look similar. This is a documented selection, not a claim to include every historical unit.
NIST measurement tables · Japanese traditional units · Mainland China and Hong Kong unit distinctions
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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