Chromatography and instrumental analysis

Chromatography and instrumental analysis

1. Paper chromatography

   • Separates mixtures
   • It has two phases, mobile and stationary
     • The stationary phase is paper
     • The mobile phase is a solvent (e.g.water)
   • Retention factor =
     • distance moved by component ___________________________________________________ distance moved by solvent

2. Gas chromatography

   • can detect small amounts
   • Seperates mixtures
   • Stationary phase = substance inside tube
   • Mobile phase = noble gas
   • After gas chromatography mass spectrometry takes place
     • this measures the MR of each individual substances

3. Other ways of separating mixtures

   • Filtration (paper & funnel) solid and substance mixed together
   • Distilation - condenser (2 liquids of different boiling points)
   • Crystalisation & evaporation (something dissolved in something)

4. Instrumental analysis

   • Disadvantages
     • results can only be interpreted by comparison
     • expensive
     • requires specialist training
   • Advantages
     • Can analyse small or trace amounts of a substance
     • quick results
     • highly accurate & sensitive