Chemical Analysis

• A pure substance is something made of only one type of substance.
• Pure substances have one specific temperature for their melting and boiling points whereas impure substances melt or boil across a range of temperatures.
• A formulation is a mixture designed for a specific purpose.
• Formulations:

  • Fuels
  • Cleaning agents
  • Paints
  • Medicines
  • Alloys
  • Fertilisers
  • Foods
• Chromatography is a process for separating coloured mixtures.
• Rf = distance moved by substance / distance moved by solvent
• When hydrogen is present, a lit spill gives a squeaky pop.
• When oxygen is present, it relights a glowing spill.
• When carbon dioxide is present, it turns lime water cloudy white.
• When chlorine is present, it bleaches damp litmus paper white.