A manufacturer separates two dyes from printer ink by paper chromatography. After the chromatogram dries, the solvent front is no longer visible.
Both dyes were on the same chromatogram.
| Dye | Rf value | Distance moved from the start line in cm |
|---|---|---|
| P | 0.60 | 4.8 |
| Q | 0.75 | ? |
What distance did dye Q move from the start line?
6.0 cm
8.0 cm
6.4 cm
3.6 cm
102 exam-style questions on OCR GCSE Chemistry 2.1 Purity and separating mixtures, covering 2.1.1 Pure substances and melting point data, 2.1.2 Relative formula mass and empirical formula, 2.1.3 Formulations as useful mixtures, 2.1.4 Techniques for separating mixtures, and 2.1.5 Chromatography and Rf values. Each one has a worked solution and a mark scheme showing where the marks go.