Paper Chromatography

• What is the purpose of paper chromatography?

  To separate substances in a mixture based on their different solubilities
• What type of processes are all separation techniques, including paper chromatography?

  Physical processes that do not involve chemical reactions
• What is the stationary phase in paper chromatography?

  The chromatography paper that does not move
• What is the mobile phase in paper chromatography?

  The solvent that moves up the paper
• Why do we use a pencil to draw the starting line in paper chromatography?

  Because pen ink could dissolve in the solvent and affect the results
• If a color produces a single spot in paper chromatography, what does that indicate?

  It indicates that the color is a single pure substance
• How does the solubility of a substance affect its movement in paper chromatography?

  More soluble substances travel further than less soluble substances
• What happens to a pure compound when subjected to different solvents in paper chromatography?

  A pure compound will always produce a single spot regardless of the solvent
• What does it mean if a color separates into multiple spots during paper chromatography?

  It means that the color is a mixture of different substances
• What are the steps involved in performing paper chromatography?

  1. Draw a pencil line near the bottom of chromatography paper.
  2. Place dots of different colors on the line.
  3. Immerse the bottom of the paper in a solvent.
  4. Allow the solvent to move up the paper and separate the colors.
  5. Observe the resulting spots to determine purity and mixtures.
• What is the significance of the RF value in paper chromatography?

  It helps identify a compound based on its position in the solvent
• What does the term 'solvent' refer to in the context of paper chromatography?

  A liquid that dissolves substances
• How does changing the solvent affect the results of paper chromatography?

  It may change the position of the spots but not the number of spots for pure substances
• What are the key facts to remember about paper chromatography?

  • All separation techniques are physical processes.
  • The paper is the stationary phase; the solvent is the mobile phase.
  • A pure compound produces a single spot in all solvents.
  • More soluble substances travel further than less soluble substances.