Chromotography

• What does paper solubility allow you to do?

  Separate substances based on their solubility
• What is the stationary phase ?

  The paper as it doesn’t move
• What is the mobile phase ?

  The solvent as it moves
• What will a pure compound produce?

  A single spot
• What will a compounds in a mixture produce?

  Different spots
• Example of chromatography 


  Red Is pure blue is a mixture

  
• Why do we use a pencil for starting line?

  A pencil is insoluble in water whilst a pen is not so using a pen could obscure the results if the ink moves up the paper
• How to calculate RF value?

  no units

  
• Why would there be no rf value for a substance ?

  Insolubility Or never been analysed