Data Source and Methodology
Authoritative source: IUPAC — Compendium of Chemical Terminology (the “Gold Book”), 2nd ed. (1997) with subsequent updates. Entry: “yield.” Updated 2014. Direct link: https://goldbook.iupac.org/terms/view/Y06746.
Tutti i calcoli si basano rigorosamente sulle formule e sui dati forniti da questa fonte.
The Formula Explained
Percent yield formula:
LaTeX: \( \%\,\text{yield} = \frac{\text{Actual yield}}{\text{Theoretical yield}} \times 100\% \)
Rearrangements:
LaTeX: \( \text{Actual yield} = \frac{\%\,\text{yield}}{100}\times \text{Theoretical yield} \)
LaTeX: \( \text{Theoretical yield} = \frac{\text{Actual yield}}{\%\,\text{yield}/100} \)
Glossary of Variables
- Actual yield — The measured amount of product obtained from a reaction (mass, moles, or volume).
- Theoretical yield — The maximum amount of product predicted by stoichiometry under ideal conditions.
- Percent yield — Efficiency metric comparing actual to theoretical yield.
- Unit type — Quantity category: mass, amount of substance, or volume. Actual and theoretical yields must use the same type.
Worked Example
How It Works: A Step-by-Step Example
Suppose your actual yield is 3.20 g and your theoretical yield is 4.00 g. Using the formula:
LaTeX: \( \%\,\text{yield} = \frac{3.20\ \text{g}}{4.00\ \text{g}} \times 100\% = 80.0\% \)
Interpretation: an 80% yield indicates moderate efficiency. Consider potential losses during isolation and purification or incomplete reaction.
Frequently Asked Questions (FAQ)
What is percent yield?
Percent yield is the ratio of actual yield to theoretical yield, expressed as a percentage that reflects reaction efficiency.
Can percent yield exceed 100%?
It can, but values over 100% usually indicate impurities, incomplete drying, or measurement errors, not a truly super-efficient reaction.
Do actual and theoretical yields need the same units?
They must represent the same quantity type (e.g., both mass). This tool converts units within the same type automatically.
Which units are supported?
Mass: µg, mg, g, kg. Amount: mmol, mol. Volume: mL, L.
Is percent yield always between 0 and 100%?
In theory yes, but experimental factors can produce values slightly below 0% (invalid data) or above 100% (contamination or weighing issues). Investigate such results.
Does the calculator handle significant figures?
It computes with full precision and displays a rounded value. You can copy the precise numeric result for reporting.
Where do the formulas come from?
They follow the IUPAC Gold Book definitions for yield and common general chemistry practice.