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SEPARATING MIXTURES - Coggle Diagram

- - - - Impurities in drugs and food can produce unwanted side effects, so purity is very important in pharmaceutical industry
    - - Chemists need pure substances to study their chemical and physical properties.
    - - Air contains useful substances such as oxygen and
      - nitrogen which have their respective applications.
      - Seawater contains table salt for cooking or preserving foods.
      - Reservoirs provide freshwater for drinking.
      - Crude oil contains useful fuels such as petrol and kerosene.
  - - - Filtration
      - Evaporation
      - Crystallisation
      - Chromatography
      - Simple distillation
    - - Fractional distillation
    - - Magnetic attraction
      - Sublimation
- - - - A filter paper has very tiny pores. Only the particles with size smaller than the pores can pass through the pores. The insoluble solids have larger particle size, so they are trapped on the filter paper,
  - - - for example
- - - - Water catchment areas
      - Desalinated water
      - Imported water from other countries
      - NEWater
- - - - It is used in printing process that uses heat to transfer dye onto paper or fabric to produce photographic prints.
  - - - At the scrap yards, a strong electromagnet is used to salvage scrap iron and steel from other junk materials.
        In mining, it is used to separate magnetic ores from none-magnetic ores.
        It is used in hospitals to remove iron splinters from patient's eyes.
- - - - This means that it will not decompose upon strong heating.
- - - - This means that it will not decompose upon strong heating.
- - - - The soluble solid that is not heat-stable decomposes on strong heating.
    - - Solutes have a high solubility in hot water than cold water. For example, the amount of copper (ll) sulfate (the solute) dissolved in 80 °c is higher than that of in 30 °c of the same amount of water.
      - When the hot saturated solution is cooled, the cooled solution cannot hold as much solute as when it was hot.
      - The excess amount of solute in a cooled solution will become undissolved and forms crystals.
- - - - Different components in a mixture have different solubility in a solvent
      - The different solubility in a solvent causes them to move at different speeds on the chromatography paper
    - - Use fine capillary tubes to place a small and concentrated sample on the paper
        
        This prevents the overlapping of components so that a clear and distinct lines or spots can be obtained.
      - The solvent front should be as high as possible. The solvent front is the line in which the solvent travels furthest up the chromatographic paper.
        
        It ensures that the components in a sample are fully separated.
      - The solvent should be below the starting line.
        
        This prevents the sample from dissolving into the solvent so that it can travel up the paper
      - The jar should be covered with a lid when a volatile solvent such as alcohols is used.
        
        It also ensures that the jar is saturated with the solvent vapour. This facilitates the movement of the solvent as it will not evaporate from the paper too quickly.
        
        It prevents the solvent from evaporating too fast.
      - Draw the starting line with a pencil and not a pen
        The starting line is the location where a sample is placed.
        
        A pencil is an element, so it is not made of dyes and will not be separated by the solvent to interfere the results.
        
        Ink is made up of dyes which can dissolve in the solvent and interfere the results.
    - - It is used to identify the contents of a mixture.
      - It is used to test the purity of a substance.
    - - It gives a fast and an accurate analysis of a sample.
      - It is able to separate complex mixtures such as food dyes
      - Only a small amount of sample is required.