Biology

20. Investigation into the separation of chloroplast pigments by chromatography

  • 00:36 Why do you grind the leaves with sand?
  • 01:05 Why must you use a pencil and not a pen for the line?
  • 01:28 Why do you need to concentrate the pigment?
  • 01:50 Why must the chromatography paper touch the solvent?
  • 02:20 Why must the pigment spot be above the solvent surface?
  • 02:30 Which pigments can you identify?

  • dark green leaves e.g. spinach, stinging nettle

  • chromatography paper or silica gel chromatography plates

  • scissors

  • pencil

  • sand

  • ruler

  • pestle and mortar

  • capillary tube

  • hair dryer

  • propanone

  • 2 x boiling tube

  • deionised water

  • petroleum ether

  • 2 x stopper

  • vial

  • pipette

Hazard Risk Control measure

Propanone: Highly flammable liquid and vapour Can cause serious eye irritation

Contact with naked flame Contact with eyes and skin

Ensure no naked flames or other sources of ignition. Ensure laboratory is well-ventilated. Eye: flood with tap water (10min)

Petroleum ether: Highly flammable liquid and vapour

Contact with naked flame

Ensure no naked flames or other sources of ignition. Ensure laboratory is well-ventilated.

Scissors

Cuts to skin

Cut away from body