Paper Chromatography

• What analytical technique is used to separate different substances in a mixture?

  Chromatography
• What is the specific type of chromatography discussed in the video?

  Paper chromatography
• What is the purpose of paper chromatography?

  To separate different dyes in an ink
• What are the steps involved in performing paper chromatography?

  1. Draw a baseline on filter paper with pencil.
  2. Add the ink sample on the baseline.
  3. Fill a beaker with a shallow amount of solvent.
  4. Place the filter paper in the solvent without submerging the baseline.
  5. Cover the beaker to prevent evaporation.
  6. Wait for the solvent to rise and separate the dyes.
  7. Remove the paper and let it dry to observe the chromatogram.
• What is a chromatogram?

  A pattern of spots left on the paper after chromatography
• What are the mobile and stationary phases in chromatography?

  The mobile phase is the solvent, and the stationary phase is the paper
• How do the different chemicals in a sample behave during chromatography?

  They dissolve in the solvent and move up the paper at different rates
• What determines how fast a chemical moves up the paper in chromatography?

  The solubility of the chemical in the solvent and its attraction to the paper
• What happens if a chemical is not soluble in the solvent used in chromatography?

  It will remain on the baseline and not move up the paper
• What is the formula for calculating the rf value in chromatography?

  rf value = distance traveled by the substance / distance traveled by the solvent
• If a pink substance traveled 6 cm and the solvent traveled 10 cm, what is the rf value?

  $0.6$
• What happens when chromatography is performed with a pure substance?

  It will not separate and will show a single spot on the chromatogram
• How can the results of chromatography vary with different solvents or papers?

  The chromatogram and rf values may change based on the mobile or stationary phase used
• Why must a chemist consider the solvent and paper type when looking up rf values?


  Because the rf values can vary depending on the solvent and paper used
• What should you do to prevent the solvent from evaporating during chromatography?

  Place a lid on top of the beaker
• What is the first step in paper chromatography?

  Draw a baseline on the filter paper with a pencil
• What is the role of the solvent in paper chromatography?

  It acts as the mobile phase that carries the substances up the paper
• How does the solubility of a chemical affect its movement in chromatography?

  More soluble chemicals spend more time in the mobile phase and move faster
• What is the significance of the baseline in paper chromatography?

  It is where the ink sample is applied before chromatography begins