Percent yield calculator explained
The percent yield calculator shows how close a reaction came to the theoretical limit so you can spot side reactions, incomplete conversions, or purification losses. Plug in any two of the three values: {experimental_yield}, {theoretical_yield}, or {percent_yield}, and the page solves for the third without extra spreadsheets.
Use it after every run so reports list both grams and efficiency, and use it up front when planning scale-ups to set realistic production targets.
How the conversion works
Percent yield compares actual and theoretical outputs:
The theoretical yield comes from stoichiometry using the limiting reagent, while the actual yield is what you collected after isolation. Solving for any variable is straightforward because the relationship is linear.
Units and conversions
| Quantity | Symbol | Units | Notes |
|---|---|---|---|
| Actual yield | g, kg | Use the isolated mass after drying. | |
| Theoretical yield | g, kg | Calculate from stoichiometry using limiting reagent moles. | |
| Percent yield | % | means quantitative conversion. |
Unit choice cancels in the ratio, so grams and kilograms deliver the same percentage as long as they match.
Worked examples
- Typical lab reaction
Limiting reagent predicts of product. You isolate .
Record the yield as in the ELN and note any byproducts.
- Solving for theoretical yield
A pilot batch produced at yield. Rearranging gives
Now you know the reaction could, at best, deliver 11.0 kg if you remove losses.
Tips and pitfalls
- Always dry the product before weighing; solvent residues inflate .
- Account for hydrates or counter-ions when computing .
- When yields exceed 100%, re-check purity or balance calibration because results above 100% often signal impurities.
- Track both molar and mass yields for organometallic reactions so you catch cases where mass looks fine but stoichiometry does not.