C3 Topic 1

  • Created by: ldupre03
  • Created on: 24-04-17 16:57
View mindmap
  • Water Testing
    • Qualitative and Quantitative testing
      • Qualitative analysis investigates the types substance present in a sample.
      • Quantitative analysis measures the amount of each substance present in a sample.
    • The test for a particular ion should be unique. It must give a positive result with only one type of ion. This way you can be sure which ions are present in a  sample.
    • Flame tests
      • Used to detect some metal cations
        • Sodium= yellow
        • Potassium= lilac
        • Calcium= red
        • copper= green/blue
    • Hydroxide precipitates
      • How do you carry out tests for metal cations using sodium hydroxide solution?
        • 1) dissolve the sample in water
          • 2) Then add a few drops of sodium hydroxide solution.
        • (Many metal cations in solutions form insoluble precipitates when this is done)
      • Aluminium and calcium ions both produce a white precipitate
        • the calcium hydroxide precipitates does not redissolve
        • the Aluminium hydroxide precipitates redissolves to form a colourless solution when excess sodium hydroxide solution is added.
      • must know the colours for these hydroxide precipitates:
        • calcium= white
        • Iron (III)= brown
        • aluminium= white
        • copper= pale blue
        • iron(II)= green
    • Calcium ions and copper (II) ions are detected using flame tests or hydroxide precipitate tests
    • Sodium ions and potassium ions are detected using flame tests


No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Water testing resources »