chromotography

• What is the aim of the practical investigation?

  To investigate paper chromatography
• What is the method for conducting the chromatography experiment?

  1. Draw a pencil line on chromatography paper.
  2. Add ink spots using a pipette or capillary tube.
  3. Place paper in a container with solvent.
  4. Remove chromatogram before solvent reaches the top.
  5. Allow to dry and measure distances travelled.
• How far from the bottom should the pencil line be drawn on the chromatography paper?

  1 - 2 cm
• What should be used to add small spots of ink to the chromatography paper?

  A pipette or capillary tube
• What should be done after placing the chromatography paper in the solvent?

  Remove it before the solvent reaches the top
• What is the purpose of measuring the distance travelled by each spot?

  To calculate the Rf value
• How is the Rf value calculated?

  Rf = distance travelled by substance / distance travelled by solvent
• What should be included in the results table for the chromatography experiment?

  • Ink
  • Spot colour
  • Distance travelled by spot (mm)
• Why are the distances travelled by each spot measured in mm?

  To provide more precise measurements
• What are the hazards and precautions in the chromatography practical?

  Hazards:

  • Harmful solvent causing skin irritation
  • Breathing difficulties from solvent fumes

  
  

  Precautions:

  • Wear gloves to avoid skin contact
  • Ensure adequate ventilation or use a fume cupboard