Paper Chromatography

• What is chromatography used for?

  To separate substances in a mixture
• What is the stationary phase in chromatography?

  Where molecules can't move, like chromatography paper
• How does the amount of separation depend on substances in chromatography?

  It depends on their distribution between phases
• What does a pure substance form in chromatography?

  One spot in any solvent
• What is the mobile phase in chromatography?

  Where molecules can move, like the solvent
• What happens to substances that are more soluble in the mobile phase?

  They move further through the stationary phase
• What is the R value in chromatography?

  The ratio of distance travelled by substance to solvent
• How is the R value calculated?

  $R =$$\frac{B}{A}$ where B is substance distance
• What does the R value depend on in chromatography?

  It changes in different solvents
• What can change in different solvents regarding chromatography?

  The number and position of spots
• What are the two phases of chromatography?

  • Stationary phase: molecules can't move (e.g., chromatography paper)
  • Mobile phase: molecules can move (e.g., water or ethanol)
• What factors affect the separation of substances in chromatography?

  • Distribution between stationary and mobile phases
  • Solubility in the mobile phase
  • Attraction to the stationary phase
• What is a chromatogram?

  • A visual representation of the separation
  • Shows spots of chemicals at different distances