Liquid-liquid mixtures

• Fractional distillation- used to separate a mixture of mixable liquids with different boiling points.
• Use of fractional distillation

  • To separate pure oxygen and pure nitrogen from liquid air
  • To separate substance in petroleum (crude oil) into useful fractions
  • To produce alcohol drinks ( obtain ethanol produced by the fermentation of glucose solution)
• Chromatography- method of separating and identifying a mixture. It is used to separate mixture of coloured or non-coloured substances that are soluble in the same solvent.
• Use of chromatography:

  • Drug abuse
  • Forgeries
  • Poisons, pesticides
  • Wether the substance is pure
  • Food dyes
• Led does not dissolve thats why we use a pencil to mark chromatogram paper instead of using an ink pen. It can affect the results.