A laboratory needs a sample that is pure liquid Z.
The accepted boiling point of liquid Z is 80 ∘C80\ ^\circ\text{C}80 ∘C. The temperature measurements are reliable.
| Sample | Boiling behaviour |
|---|---|
| A | Boiled at a constant temperature of 76 ∘C76\ ^\circ\text{C}76 ∘C |
| B | Boiled over a range from 77 ∘C77\ ^\circ\text{C}77 ∘C to 80 ∘C80\ ^\circ\text{C}80 ∘C |
Evaluate whether either sample is suitable for the laboratory.
113 exam-style questions on AQA GCSE Chemistry 8.1 Purity, formulations and chromatography, covering 8.1.1 Pure substances, 8.1.2 Formulations, and 8.1.3 Chromatography. Each one has a worked solution and a mark scheme showing where the marks go.