A laboratory checks three samples supplied as pure liquids. All boiling temperatures were measured under the same conditions.
| Substance | Accepted boiling point in ∘C^\circ\text{C}∘C |
|---|---|
| Hexane | 69 |
| Ethyl ethanoate | 77 |
| Water | 100 |
| Sample | Substance named on the label | Measured boiling temperature in ∘C^\circ\text{C}∘C |
|---|---|---|
| A | Hexane | 69 |
| B | Water | 77 |
| C | Ethyl ethanoate | 75 to 79 |
Use both tables.
Give the letter of the sample for which the result supports both that it is pure and that the substance named on its label is correct.
Give two reasons for your answer.
The laboratory manager suggests that changing the labels could resolve the problem with both samples B and C.
Explain whether changing only the label could make each sample consistent with a correctly labelled pure substance.
Use data from both tables.
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.