Chromatography

    Cards (5)

    • Phases of Chromatography
    • The Rf value is used to compare how far different substances travel along the chromatogram, allowing us to identify them based on their distances from the starting point.
    • Rf Formula
    • Required Practical- Chromatography
    • Required Practical- Chromatography
      1. Use a pencil to draw a horizontal line near the bottom of the chromatography paper.
      2. Place samples of known food colourings (A-D) next to an unknown substance (X) on the ‘start line’.
      3. Place the paper in a beaker containing a small volume of solvent.
      4. Let the solvent move to a few cm below the end of the paper.
      5. By comparing spots produced by X with those produced by A-D, you will be able to identify the unknown substance.