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Redox Equilibria

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    Given the following redox reactions:

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    How many moles of iron (II) ethandioate FeC2O4 are oxidised by 1 mol of dichromate Cr2O72–(aq)?

    (I thought the answer was 2. However the mark scheme says 3, and does not explain why.)
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    :confused: I dont know, sorry

    I would have said two, as you've got 6e- on the LHS, and 3e- on the right, so I would have doubled the number of moles on the RHS, giving 2 moles...

    sorry, that is of no use what so ever...

    best to ask teacher tomorrow at college perhaps?

    unless someone else can shed some light on this. im curious now, i wonder what we're doing wrong??
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    (Original post by HeatherJarvo)
    :confused: I dont know, sorry

    I would have said two, as you've got 6e- on the LHS, and 3e- on the right, so I would have doubled the number of moles on the RHS, giving 2 moles...

    sorry, that is of no use what so ever...

    best to ask teacher tomorrow at college perhaps?

    unless someone else can shed some light on this. im curious now, i wonder what we're doing wrong??
    Thank you. I asked my teacher, he said the mark scheme got it wrong.
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    (Original post by Gattsu)
    Thank you. I asked my teacher, he said the mark scheme got it wrong.
    that's a scary thought isn't it? It's possible to lose marks on the exam by getting the answer correct.... eek!!
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    (Original post by Gattsu)
    Given the following redox reactions:

    Click image for larger version. 

Name:	eq_0d8175.gif 
Views:	49 
Size:	2.6 KB 
ID:	138593

    How many moles of iron (II) ethandioate FeC2O4 are oxidised by 1 mol of dichromate Cr2O72–(aq)?

    (I thought the answer was 2. However the mark scheme says 3, and does not explain why.)

    (Original post by HeatherJarvo)
    :confused: I dont know, sorry

    I would have said two, as you've got 6e- on the LHS, and 3e- on the right, so I would have doubled the number of moles on the RHS, giving 2 moles...

    sorry, that is of no use what so ever...

    best to ask teacher tomorrow at college perhaps?

    unless someone else can shed some light on this. im curious now, i wonder what we're doing wrong??
    Couldnt figure out how you form iron (II) ethandioate FeC2O4 in the first place !?
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    (Original post by arvin_infinity)
    Couldnt figure out how you form iron (II) ethandioate FeC2O4 in the first place !?
    Why can you not form it?

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    (Original post by thegodofgod)
    Why can you not form it?

    Oh no..I meant , how you form it according the the equation given to you
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    (Original post by arvin_infinity)
    Oh no..I meant , how you form it according the the equation given to you
    Fe2+ + (COOH)2 --> [Fe(COO)2] + 2H+
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    (Original post by charco)
    Fe2+ + (COOH)2 --> [Fe(COO)2] + 2H+
    COOH is not given to us !!!

    I guess I misunderstood the question

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