Separation Techniques

• solute


  gas or solid that dissolves in a liquid
• solvent


  the liquid the solid or gas dissolves in
• solution


  mixture of a solid or gas dissolved in a liquid that stays evenly mixed
• An element is a pure substance that contains only one type of atom.
• An element cannot be separated into simpler materials (except nuclear reactions).
• Compounds cannot be separated by physical means.
• saturated solution


  maximum mass of a solute that will dissolve in the solvent
• solubility


  mass of solute that will dissolve in 100g of water to make a saturated solution
• Factors that affect solubility:

  • type of solvent
  • type of solute
  • temperature of solvent
• dissolve


  solute mixed with a solvent to form a solution
• insoluble


  substance that does not dissolve in a given solvent
• soluble


  substance that will dissolve in a given solvent
• solute


  substance that dissolves in a solvent to make a solution (e.g in saltwater, this substance is the salt)
• solution


  a mixture of two or more substances formed when a solute dissolves in a solvent
• solvent


  substance in which a solute dissolves (e.g in salt water, the substance is salt)
• filtration


  separate an insoluble solid from a liquid
• The holes in the filter paper must be small enough to only let the liquid particles through and not the solid particles.
• filtrate


  liquid that passes through the filter paper
• residue


  insoluble solid left behind on the filter paper
• Method of filtration:

  1. Add water to the mixture of sugar and tea leaves in the beaker.
  2. Stir the mixture with a stirring rod to dissolve the sugar
  3. Filter the mixture, using the filter paper and a funnel into a conical flask.
  4. The sweetened tea solution passes through the filter paper and collects in a conical flask.
  5. The tea leaf residue collects on the filter paper.
• evaporation


  separate a dissolved (soluble) solid from a solution using heat to turn the solvent into a gas
• simple distillation


  separates the solvent out from the solution, leaving the solute behind (e.g separate and collect the water from seawater)
• Sequence of processes in distillation:

  heating --> evaporation --> cooling --> condensing
• What happens during distillation:

  1. Heat the salt solution in the flask to the boiling point of the water with a Bunsen burner/ flask heater.
  2. The solution begins to boil.
  3. The boiling water starts to evaporate and turns into steam that rises up the flask.
  4. The steam travels down the cold, glass condenser.
  5. The steam condenses into pure, liquid water when it hits the cold surface of the condenser.
  6. The pure water collects into a beaker at the end of the condenser.
  7. The salt is left behind in the heated flask.
  8. Dry the wet salt in an oven/ by the window.
• The more temperature that increases, the more solubility increases.
• chromatography


  separate and identify soluble substances in a mixture from one another
• Substances that are more soluble in the solvent being used will travel further up the chromatography paper.
• Mixtures will produce multiple spots.
• A pure substance will produce a single spot on the chromatogram.