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    Hey, I'm really stuck on a question about combining half cells
    Firstly I combined the two half cells I was given;

    F2(g) + 2e- ----> 2F- (aq) E = +2.87 V
    2H+ (aq) + 2e- -----> H2 (g) E = 0.00 V

    As far as I know, you have to flip the hydrogen half cell?
    that would give;

    H2 (g)------> 2H+ (aq) + 2e-

    Then the overall equation would be;

    F2 (g) + H2 (g) ---> 2H+ (aq) + 2F-(aq)


    Now..... Is that right?
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    (Original post by ManicMetalhead)
    Hey, I'm really stuck on a question about combining half cells
    Firstly I combined the two half cells I was given;

    F2(g) + 2e- ----> 2F- (aq) E = +2.87 V
    2H+ (aq) + 2e- -----> 2H2 (g) E = 0.00 V

    As far as I know, you have to flip the hydrogen half cell?
    that would give;

    2H2 (g)------> 2H+ (aq) + 2e-

    Then the overall equation would be;

    F2 (g) + 2H2 (g) ---> 2H+ (aq) + 2F-(aq)


    Now..... Is that right?
    It's not balanced.. count the hydrogens
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    (Original post by charco)
    It's not balanced.. count the hydrogens
    Ooops! that's me typing it wrong :P

    But minus that, is that right or not?
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    (Original post by ManicMetalhead)
    Ooops! that's me typing it wrong :P

    But minus that, is that right or not?
    Apart from that it's OK

    F2(g) + H2(g) ---> 2H+ (aq) + 2F-(aq)
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    Chemistry reference.... oh wait!
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    (Original post by joe3469)
    Chemistry reference.... oh wait!
    huh?
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    (Original post by charco)
    Apart from that it's OK

    F2(g) + H2(g) ---> 2H+ (aq) + 2F-(aq)


    cool, okay.
    What do you know about the Nernst equation?
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    (Original post by ManicMetalhead)
    huh?
    Don't worry
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    (Original post by ManicMetalhead)
    cool, okay.
    What do you know about the Nernst equation?
    What do you want to know?
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    (Original post by charco)
    What do you want to know?
    Okay, I'm trying to calculate the E-cell of the reaction above yeah?
    I've got the concentrations of the hydrogen and fluorine ions (0.4 mol dm-3 and 0.3 mol dm-3 respectively)
    How would you work out Q?


    Since as far as I know it is normally calculated by dividing one by the other, but I couldn't seem to do it in this cell?


    If that makes sense?
 
 
 
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