Topic 2 - States of Matter and Mixtures

• Solid


  • Particles arranged in fixed rows (lattice)
  • Strong forces of attraction between particles
  • Low particle energy (vibrating)
• Liquid


  • Random arrangement of particles
  • Particles can flow and move freely over eachother covering the bottom of a container
  • Moderate particle energy
• Gas


  • No fixed shape and randomly bounce off surfaces filling a container
  • Low forces of attraction between particles
  • High particle energy
• Melting


  Transition from solid to liquid
• Boiling


  Transition from liquid to gas
• Condensing


  Transition from gas to liquid
• Freezing


  Transition from liquid to solid
• Sublimation


  Transition directly from solid to gas
• Deposition


  Transition directly from gas to solid
• Pure substance


  Made up of one element or compound
• Mixture


  Multiple substances mixed together but not bonded
• Pure substances have a fixed melting and boiling point
• Mixtures/impure substances melt and boil over a range of temperatures
• Filtration


  1. Pour mixture into funnel lined with filter paper

  2. Insoluble solid stays on top as residue

  3. Liquid (filtrate) passes through
• Crystallization


  • Mixture is heated, some of the solvent evaporates, leaving behind a saturated solution– one in which no more solid can dissolve at that temperature
  • Saturated solution cools and solid is left behind as crystals which form (can be separated out with filtration)
  • Pat them dry and leave
• Chromatography


  1. Draw mixture spots on origin line of chromatography paper

  2. Dip in solvent, which moves up paper and separates mixture

  3. Calculate RF values to identify substances
• Simple distillation


  1. Heat mixture, vapour condenses in condenser down the delivery tube and collects in flask

  2. Works for liquids with very different boiling points
• Fractional distillation


  • Use fractionating column to separate liquids with similar boiling points
  • The substance is boiled till vapour is formed
  • Vapour condenses when they reach a part of the column that is below the temperature of their boiling point
  • The liquids which condense in the column drip back into the flask
  • Vapour at the top of the fractioning column enters the condenser where it is changed to a liquid
  • Distillates collected over a narrow temperature range are known as fractions
• Making water potable


  1. Sedimentation - let large particles settle

  2. Filtration - remove fine particles

  3. Chlorination - kill microorganisms