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Homework Help: Redox Reaction

  1. Feb 10, 2007 #1

    danago

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    1. The problem statement, all variables and given/known data
    Excess acidified potassium permanganate is added dropwise to an ammonium iron(II) sulfate solution. Write an overall redox equation for this process.

    2. The attempt at a solution
    Well im not really sure what to do. I dont know what products are being formed. What should i do in a situation like this?
     
  2. jcsd
  3. Feb 10, 2007 #2
    Start with a balanced equation. Were you given the rules to follow for a redox reaction?
     
  4. Feb 10, 2007 #3

    Gokul43201

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    What is the one thing that you neeed to know about potassium permanganate?
     
  5. Feb 10, 2007 #4

    danago

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    How do i write a balanaced equation though? I dont know what the products are
     
  6. Feb 10, 2007 #5

    danago

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    Its soluble in water?
     
  7. Feb 10, 2007 #6

    Gokul43201

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    Lots of things are soluble in water.

    I quote from the first paragraph of the wiki on potassium permanganate:

     
  8. Feb 10, 2007 #7

    danago

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    Ok, so its an oxidising agent, and therefore, itself reduced. I think this is the correct equation for its reduction:

    [tex]
    MnO_4 ^ - _{(aq)} + 8H^ + _{(aq)} + 5e^ - \to Mn^{2 + } _{(aq)} + 4H_2 O_{(l)}
    [/tex]

    Would i just combine that with the half equation of iron (II) being oxidised to iron (III) ions?
     
  9. Feb 11, 2007 #8

    Gokul43201

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    Yup, you got it! :approve:
     
  10. Feb 11, 2007 #9

    danago

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    Ahh ok. Thanks :)
     
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