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    Hello,

    In the Nelson Thornes textbook, it gives the example of dipping a zinc rod into a zinc sulfate solution. The following eqm is set up:
    Zn(s) + (aq) <--> Zn2+(aq) + 2e-
    It states that the eqm lies far to the left and that the zinc acquires a negative charge, but why is that if the reverse reaction is occurring more? Aren't the electrons being used up? If it's referring to Zn2+ gaining electrons to become neutral, what is becoming negatively charged?

    Thanks and sorry - it's probably just me misunderstanding!
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    Basically the zinc is the more positive electrode, all electrode potential equations are set up like that. If it lies to the left it is telling you it is the more positive side and gains an electron from the negative electrode

    I think Zn2+ gains 2e- and goes to Zn, so more zinc is deposited on the electrode, so whatever the negative electrode is which lies more to the right ( looses electrons) and is oxidised is donating the electrons to the zinc to be reduced. Nothing is becoming negatively changed it just goes back to neutral..

    I hope I've explained this okay, I'm trying to understand this topic myself!
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    Thanks for the reply! I think you're right - it was a good explanation! The only thing is that there is no other electrode, so presumably electrons exist in the solution (zinc sulfate) itself(?)

    It seems straight forward on the surface, but it's actually quite complicated as a topic!

    (Original post by K3001N)
    Basically the zinc is the more positive electrode, all electrode potential equations are set up like that. If it lies to the left it is telling you it is the more positive side and gains an electron from the negative electrode

    I think Zn2+ gains 2e- and goes to Zn, so more zinc is deposited on the electrode, so whatever the negative electrode is which lies more to the right ( looses electrons) and is oxidised is donating the electrons to the zinc to be reduced. Nothing is becoming negatively changed it just goes back to neutral..

    I hope I've explained this okay, I'm trying to understand this topic myself!
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    (Original post by elf03)
    Thanks for the reply! I think you're right - it was a good explanation! The only thing is that there is no other electrode, so presumably electrons exist in the solution (zinc sulfate) itself(?)

    It seems straight forward on the surface, but it's actually quite complicated as a topic!

    If there is no other electrode presumably the solution would contain both!!
    It is quite a complicated topic, I have no idea how to work out the hydrogen fuel cell :/
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    Okay, thank you! Ah, I must look at that section too! Good luck with revision :-)

    (Original post by K3001N)
    If there is no other electrode presumably the solution would contain both!!
    It is quite a complicated topic, I have no idea how to work out the hydrogen fuel cell :/
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    (Original post by elf03)
    Okay, thank you! Ah, I must look at that section too! Good luck with revision :-)
    Thank you! you too!
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    Some of the zinc atoms will lose their electrons and go into the solution. The electrons remain on the zinc metal electrode itself so the electrode becomes negatively charged and is sorrounded by the positive zinc ions. Dynamic equilibrium is reached when the rate at which zinc atoms are turning into zinc ions by losing electrons is the same as the rate at which the ions in the solution are turning into zinc atoms by gaining the 'spare' electrons on the surface of the zinc metal.
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    Ah, thanks so much!

    (Original post by B_9710)
    Some of the zinc atoms will lose their electrons and go into the solution. The electrons remain on the zinc metal electrode itself so the electrode becomes negatively charged and is sorrounded by the positive zinc ions. Dynamic equilibrium is reached when the rate at which zinc atoms are turning into zinc ions by losing electrons is the same as the rate at which the ions in the solution are turning into zinc atoms by gaining the 'spare' electrons on the surface of the zinc metal.
 
 
 
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