Paper Chromatography

• What are some methods to separate mixtures?

  Filtration, crystallisation, simple distillation, fractional distillation, and chromatography
• What determines the method chosen to separate a mixture?

  The type of mixture
• What is chromatography used for?

  • To separate different substances dissolved in a liquid
  • Often used for colored substances like food colorings, inks, dyes, or plant pigments
• What is a soluble substance?

  A substance that can dissolve in a solvent
• Why is sugar considered soluble in water?

  Because it dissolves to form a sugar solution
• What are the two phases in chromatography?

  • Stationary phase: the paper that does not move
  • Mobile phase: the solvent that moves through the paper
• What is the stationary phase in paper chromatography?

  The absorbent paper
• What is the mobile phase in chromatography?

  The solvent that moves through the paper
• How do different substances in a mixture behave in chromatography?

  They are attracted to the two phases in different proportions
• What does a chromatogram represent?

  The results of separating mixtures by chromatography
• How can a chromatogram distinguish between pure and impure substances?

  A pure substance produces one spot, while an impure substance produces two or more spots
• What indicates that two substances are likely the same when comparing chromatograms?

  If they produce the same number of spots that match in color and travel the same distance
• What are the steps involved in paper chromatography?

  1. Draw a pencil line on chromatography paper
  2. Dot ink or plant dye along the line
  3. Lower the paper into a solvent
  4. Observe the dye spreading up the paper