mixtures and sEpAraTiON EW

• Mixture


  Substance made by mixing other substances together
• Mixtures


  • Classified by whether the substances in them are solids, liquids or gases
• Types of mixtures


  • Suspension
  • Colloid
  • Solution
• Suspension


  Mixture of two substances that separate if mixture is not stirred (e.g. sand mixed with water)
• Colloid


  One substance is dispersed in another substance and cannot be separated easily (e.g. whipped cream)
• Solution


  Solid dissolves in the liquid, making mixture clear or transparent, contains dissolved solids
• Solvent


  Liquid in the solution (e.g. water)
• Solute


  The substance that is dissolved in a solvent (which means it's soluble) (e.g. sand, salt)
• Color chromatography


  Technique used to separate substances dissolved in a mixture
• Paper chromatography


  1. Dots of ink are placed at the bottom of the chromatography paper on the baseline

  2. The solvent carries the colours up the paper and they will travel up at different rates

  3. If any of them are not soluble it will not be able to dissolve or move up
• If the solvent is more soluble


  It will be carried up faster
• If the solvent is less soluble


  It will be carried up slower
• Separation techniques


  • Chromatography
  • Filtration
  • Evaporation
  • Heating to dryness
• Filtration


  Process separating solid from a liquid by passing it through a filter
• Heating to dryness


  Heating a solution until all the solvent has evaporated
• The mass of solution is the same as the mass of the dissolved substance + mass of liquid at the start
• There is a limit to how much solute you can dissolve in a solvent, if you add more solute the extra will sink to the bottom and stay dissolved, this is called saturated