All calculatorsPercent Yield Calculator
Compute percent yield, actual yield, or theoretical yield. Enter amounts in grams or moles (use molar mass to convert). See steps, a mini bar chart, and a percent gauge.
Background
Percent yield measures efficiency: % yield = (actual / theoretical) × 100. Theoretical yield comes from stoichiometry (balanced equation & limiting reagent), while actual yield is what’s isolated experimentally.
How this calculator works
- Definition: % yield = (actual / theoretical) × 100.
- Input rules: Provide any two of {actual, theoretical, percent}; we solve the third.
- Units: Compare on the same basis — both grams or both moles. If you enter grams, use molar mass to convert.
- Tip: Theoretical yield is set by stoichiometry and the limiting reagent.
Formula & Equation Used
Percent yield: % = (actual / theoretical) × 100
Rearrangements: actual = (%/100)·theoretical; theoretical = actual / (%/100)
Example Problems & Step-by-Step Solutions
Example 1 — Compute percent yield
Actual = 7.20 g, Theoretical = 9.00 g → % = (7.20/9.00)×100 = 80.0%.
Example 2 — Compute actual yield
% = 92.0%, Theoretical = 25.0 g → Actual = 0.92×25.0 = 23.0 g.
Example 3 — Mixed units (grams ↔ moles)
Actual = 3.50 g of glucose (M=180.16 g·mol⁻¹) → 0.0194 mol.
Theoretical = 0.0250 mol → % = (0.0194/0.0250)×100 ≈ 77.6%.
Frequently Asked Questions
Q: Why can percent yield exceed 100%?
Usually due to impurities or solvent; the measured mass is artificially high.
Q: Do I always need molar mass?
Only if you compare grams to moles. If both amounts are in moles (or both in grams), you can compute directly.
Q: Is theoretical yield the same as limiting reagent?
The limiting reagent determines the theoretical yield via stoichiometry; the values aren’t the same, but they’re linked.
