Paper chromatography

• Mixture


  A combination of two or more substances that are not chemically bonded together and can be separated
• Separation techniques


  • Used to separate a variety of mixtures into individual substances
• Physical change


  A change that does not involve a change in the chemical composition of a substance
• Chemical change


  A change that involves the rearrangement of atoms to produce new substances with different properties
• Paper chromatography


  1. Spot mixture on pencil line

  2. Place paper in solvent

  3. Solvent carries mixture up paper

  4. Components separate at different rates
• Retardation factor (Rf)


  Distance moved by the compound ÷ distance moved by the solvent
• The Rf value is a measure of how soluble a particular substance is in a given solvent
• The Rf value of a particular compound is always the same if the chromatography has been carried out in the same way
• Locating agent


  A substance used to detect another substance by making it visible