P3.5—Calculations, reasoning and significant figures
- Syllabus
- 9701–2028–2029
- Objective
- P3.5
- Level
- AS
Show calculation steps and round only after the reasoning is complete
Show the equation, substituted values and key rearrangement so the reasoning can be checked. Give the final answer to a sensible number of significant figures, normally no more than the least precise input (or one extra where instructed).
Keep calculator precision during intermediate steps, attach units and check the order of magnitude before rounding.
If 0.250 mol is divided by 0.100 dm³, show c = n/V = 2.50 mol dm⁻³; the three significant figures reflect the inputs.
Do not round each intermediate line or report a long calculator string as if it were more accurate data.
ConceptA-Level CAIE Chemistry AS