All calculations
Concentration in g/dm3
Quantitative chemistry
AQA 8462
ORIGINAL
concentration(g/dm3) = mass(g) / volume(dm3)
This concentration is mass per solution volume, so no moles or Mr are needed.
Verified against AQA 8462 (2026 spec)
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
3 marks
A solution contains 6.0 g of sodium chloride in 250 cm3 of solution. Calculate its concentration in g/dm3.
Do the calculation on paper first — then mark it.
Where the marks get lost
- Using 250 directly instead of converting cm3 to dm3.
- Using the solvent volume instead of the final solution volume.
Exam tip: For g/dm3, the top line is grams and the bottom line must be dm3.
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 — your first lesson is free.