A student made 6.0 g of product in a reaction that should theoretically produce 8.0 g. Calculate the percentage yield.
[2 marks]
Total for this question: 2
All calculations
Percentage yield
Quantitative chemistry
AQA 8462
ORIGINAL
percentage yield = (actual yield / theoretical yield) x 100
Actual over theoretical. An apparent yield above 100% means the measured 'product' is not a pure, dry product or the calculation/measurement is wrong.
Board and spec code confirmed against AQA 8462 · registry checked 2026-07-17How this checking works
Work it, then mark it
Do each calculation on paper first, then reveal the mark scheme and tick the marks you actually earned — the same way you should mark past papers.
Q1
Do the calculation on paper first — then mark it.
Where the marks get lost
- Dividing the theoretical yield by the actual yield (it's actual on top).
- Treating a yield above 100% as arithmetic only — wet product, impurities or contamination can make the measured mass too high.
- Confusing percentage yield (about the experiment) with atom economy (about the equation).
Exam tip: Actual yield goes on top. If the result exceeds 100%, check the fraction and arithmetic, but also ask whether the product was fully dry and pure.
Calculations are the most trainable marks in chemistry
They come up every paper and reward a clean method. Send me one you keep dropping marks on. Free intro call, then a free first lesson.
Stuck on percentage yield?
Everything here stays free. If percentage yield is where the marks keep going, I teach it one to one from the mark schemes. Free intro call, then a free first lesson.