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C.8 - Chemical Analysis - Coggle Diagram

- - - - Its faster (usually automated - with a computer)
      - More accurate
      - More sensative - tests can even be done with tiny amounts of a sample
- - - - Flame Test
        
        Steps
        
        Sterilise a platinumn wire loop in some dilute hydrochloric acid and then use some distilled water to rinse it
        
        Dip the wire into the compound you are trying to test
        
        Hold the wire into the hottest part of the bunsen burner (blue part)
        
        A distinct flame colour will be produced
        
        Usually as a metal burns they produce a flame with each metal producing a differently coloured flame to others
        
        Colours produced by each metal...
        
        Lithium - Crimson Red
        
        Sodium - Yellow
        
        Potassium - Lilac
        
        Calcium - Orange/Red
        
        Copper - Green
      - However if there are multiple metals the colours mix and then mask meaning its harder to differentiate.
        
        Metal Hydroxide Test
        
        React solution with NaOH and see what colour it turns. This is viable as some metal ions for coloured precipitats when they react with hydroxide ions.
        
        Ca - White
        
        Fe(II) - Green
        
        Fe(III) - Brown
        
        Mg - White
        
        Al - White (initally until excess NaOH is added then it turns colourless)
        
        Cu - Blue
  - - - Formula = Carbonate + Acid --> Salt + Carbon dioxide + water
      - Test for Carbon Dioxide if limewater turns cloudy/bubbles then CO2 is present
    - - Add Barium to the solution
      - Formula = Ba2+ + SO4(2-) + BaSO4
      - If a white precipitate forms this indicates a positive result
      - Add dilute HCL to the solution to remove impurities
      - Add Barium Chloride which contains the Barium ions that form the white precipitate
    - - Br,I,Cl
      - Add dilute nitric acid which remove impurites
      - Add silver nitrate which contains the ions to form a white precipitate
      - I - Yellow Precipitate
      - Cl - White Precipitate
      - Br - Cream Precipitate