Mixtures

• What is a mixture?

  A substance made up of more than one type of atom not chemically combined
• What are the 4 separation techniques for mixtures?

  Chromatography

  Filtration

  Distillation

  Evaporation
• What is the equation for Rf value?

  Rf = Distance moved by substance/Distance moved by solvent front
• What does chromatography separate?

  Mixtures of soluble substances
• What does filtration separate?

  An insoluble solid from a liquid
• What does evaporation separate?

  A soluble solid from a liquid
• What does distillation separate?

  Mixtures containing two liquids
• Why must the base line in chromatography be drawn in pencil?

  Ink runs in water
• Why must the solvent be below the base line in chromatography?

  Inks would run downwards
• What happens if inks rise to the same level?

  The substances are the same
• What happens if an ink stays on the base line?

  The inks are insoluble