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Homework Help: Err, 'kid' chemistry question. HELP!

  1. Aug 18, 2007 #1
    Question :
    Air sample sujected to following tests. The anhydrous CuSO4 turned blue, the acidified KMnO4 was decolourised and white ppt was seen in limewater.

    Which of the following sets of gasas was present in the air sample?

    a) SO2, CO2 and H2O
    b) SO2, CO and H2O
    c) CO, H2 and H2O
    d) CO2, H2O and CO

    someone please tell me and explain why.

    thank you.
  2. jcsd
  3. Aug 20, 2007 #2


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    Please read the sticky thread at the top of this subforum. We can not help you unless you first show your own effort.
  4. Aug 21, 2007 #3
    does saying it's either a or d because co2 is produced when the limewater turns chalky constitute as showing my own effort?
  5. Aug 21, 2007 #4


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    It's not asking what is produced, it is asking what is absorbed / reacted.
    But you are correct by accident, CO2 + Ca(OH)2 gives you a precipatate of CaCO3

    'anhydrous' CuSO4 gives you a clue about the water but since water is in all the answers that doesn't really help.
    You just have to think what does a strong oxidiser like KmnO4 do?
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