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Homework Help: Electroliz potential question

  1. Jan 29, 2010 #1
    35hh4oz.jpg
    what is the standard potential for the given x
    ?
     
  2. jcsd
  3. Jan 29, 2010 #2

    Borek

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    Write Nernst equations for both half cells.
     
    Last edited by a moderator: Aug 13, 2013
  4. Jan 29, 2010 #3
    i cant interpret it
    on the left
    Pb gives 2 electrons
    on the right H3O+ give H+
    what is pt(s)
    ?
     
  5. Jan 30, 2010 #4

    Borek

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    Solid (and inert) platinum electrode. Half cell is H+/H2, Pt is only a contact.
     
    Last edited by a moderator: Aug 13, 2013
  6. Jan 30, 2010 #5
    so i have
    Pb=Pb+2e
    H_2+H^+=H_3O^+

    what to do now
    ?
     
    Last edited: Jan 30, 2010
  7. Jan 30, 2010 #6

    Borek

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    Read my answers again? I hate to repeat myself.
     
    Last edited by a moderator: Aug 13, 2013
  8. Jan 30, 2010 #7
    "Write Nernst equations for both half cells."

    there are 4 ingredients for 4 given concentrations
    i dont know how to build the expression for equlibrium.
    and i dont know the total E0

    ven if i would want to find the E0
    i cant construct a total responce because the first give electrons and the other give H+
     
  9. Jan 30, 2010 #8

    Borek

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    Write reaction equations for both half cells. These are separate reactions, and they are both producing or consuming electrons.
     
    Last edited by a moderator: Aug 13, 2013
  10. Jan 30, 2010 #9
    no

    one consuumes electrons the other comsumes hirogen
     
  11. Jan 30, 2010 #10

    Borek

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    Try to write reactants and products for both.
     
    Last edited by a moderator: Aug 13, 2013
  12. Jan 30, 2010 #11
    i have
    Pb=Pb+2e
    H_2+H^+=H_3O^+

    what to do now
    ?
     
  13. Jan 30, 2010 #12

    Borek

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    The second one is wrong. Hydrogen is oxidized to H+ in presence of water.
     
    Last edited by a moderator: Aug 13, 2013
  14. Jan 30, 2010 #13
    i dont know how to intepret it
     
  15. Jan 30, 2010 #14

    Borek

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    Let's try with something simpler - hydrogen oxidized to H+.
     
    Last edited by a moderator: Aug 13, 2013
  16. Jan 30, 2010 #15
    H=H^+ +e
     
  17. Jan 30, 2010 #16

    Borek

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    Apart from the fact that hydrogen is not H, that's correct - as you see, electrons are involved after all. What happens to H+ in water?
     
    Last edited by a moderator: Aug 13, 2013
  18. Jan 30, 2010 #17
    dont know
     
  19. Jan 30, 2010 #18

    Borek

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    What is H3O+?

    --
    methods
     
  20. Jan 30, 2010 #19
    ok so it transfrmed into H3o+
     
  21. Jan 30, 2010 #20
    but i cant solve this question
     
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