experiments

• what is chromatography?


  the chemical analysis technique used to separate substances in mixtures
• what is chromatography used for?


  to separate a mixture of soluble substances in liquids
• what is the name given for the pencil line?

  the baseline
• why should you use pencil for the baseline and not pen?

  pen ink would dissolve in the solvent and move up the paper
• should the baseline be submerged in the solvent?


  no
• what are some solvents commonly used in chromatograhpy?


  • water
  • ethanol
• what is the resulting paper we end up with? (chromatography)


  a chromatogram
• what does the 'mobile phase' refer to?


  molecules that can move
• what is the mobile phase in paper chromatography?


  the solvent
• fill in the gaps

  a substance which is _____ soluble in the mobile phase will spend more time in the mobile phase. this means it will move _____ and travel a _____ distance up the paper


  more

  faster

  further
• a substance which is less soluble in the mobile phase will spend more time in what phase?

  what will this mean?

  • stationary
  • slower
• formula for the rf value


  distance travelled by the substance

  ---------------------------------

  distance travelled by the solvent
• what are the steps of simple distillation?


  1. a solution is heated, usually using bunsen burner
  2. the liquid in the mixture evaporates into a gas
  3. the gas is cooled by a water jacket, and condenses into a liquid, which then flows into the beaker
• fractional distillation can separate a mixture of several liquid that each have different


  boiling points
• which is the correct order for fractional distillation?


  1. boiling flask
  2. fractioning column
  3. condenser
  4. beaker
• how would you isolate pure water from salt water?


  simple distillation