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    I need help writing the half equations for these two reactions

    ClO- → ClO3-, ClO- → Cl-

    i wrote

    Cl0- + 2H20 --> Cl03- + 4H+ + 4e-
    2Cl0- + 4H+ + 4e- --> 2Cl- + 2H20

    I though the answer was Cl0- --> Cl03- + 2Cl-

    but it is 3ClO- → 2Cl- + ClO3-

    can someone please explain this to me

    Thanks
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    (Original post by zoedhin)
    I need help writing the half equations for these two reactions

    ClO- → ClO3-, ClO- → Cl-

    i wrote

    Cl0- + 2H20 --> Cl03- + 4H+ + 4e-
    2Cl0- + 4H+ + 4e- --> 2Cl- + 2H20

    I though the answer was Cl0- --> Cl03- + 2Cl-

    but it is 3ClO- → 2Cl- + ClO3-

    can someone please explain this to me

    Thanks
    Well the answer is balanced and the oxidation state of chlorine in ClO3- is +5
    I'll post working
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    (Original post by notathuggee)
    Well the answer is balanced and the oxidation state of chlorine in ClO3- is +5
    I'll post working
    Ohhh ok that makes sense! i didn't realise that the answer had to be balanced
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    (Original post by notathuggee)
    Well the answer is balanced and the oxidation state of chlorine in ClO3- is +5
    I'll post working
    Can you help me with this one

    please

    a) PbO2 → Pb2+, Cl- → Cl2

    my final answer is

    Pb02 + 4H+ + 2cl- --> Pb2+ +cl2 + 2H20

    but the answer is wrong can you tell me why?

    the correct answer is

    PbO2 + 4H+ + 2Cl- → Pb2+ + 2Cl- + 2H2O

    Thanks
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    (Original post by notathuggee)
    Well the answer is balanced and the oxidation state of chlorine in ClO3- is +5
    I'll post working
    Name:  chloros.jpg
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    (Original post by zoedhin)
    Can you help me with this one

    please

    a)PbO2 → Pb2+, Cl- → Cl2

    my final answer is

    Pb02 + 4H+ + 2cl- --> Pb2+ +cl2 + 2H20

    but the answer is wrong can you tell me why?

    the correct answer is

    PbO2 + 4H+ + 2Cl- → Pb2+ + 2Cl- + 2H2O

    Thanks
    That correct answer isn't balanced in charge???
    2+ on LHS and 0 on RHS

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    (Original post by C0balt)
    That correct answer isn't balanced in charge???
    2+ on LHS and 0 on RHS

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    that stems from the Pb tetracation being unstable and forming the Pb dication
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    (Original post by notathuggee)
    that stems from the Pb tetracation being unstable and forming the Pb dication
    Is that in AS?

    Posted from TSR Mobile
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    (Original post by zoedhin)
    Can you help me with this one

    please

    a) PbO2 → Pb2+, Cl- → Cl2

    my final answer is

    Pb02 + 4H+ + 2cl- --> Pb2+ +cl2 + 2H20

    but the answer is wrong can you tell me why?

    the correct answer is

    PbO2 + 4H+ + 2Cl- → Pb2+ + 2Cl- + 2H2O

    Thanks
    pic should be attached
    Attached Images
     
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    (Original post by notathuggee)
    pic should be attached
    Ohh ok im a bit confused tho

    Whats the correct answer then?
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    (Original post by notathuggee)
    pic should be attached
    is it

    Pb02 + 4H+ + 2cl- --> Pb2+ +cl2 + 2H20
    or

    Pb02 + 4H+ + 2cl- --> Pb2+ +2cl- + 2H20
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    (Original post by zoedhin)
    Pb02 + 4H+ + 2cl- --> Pb2+ +cl2 + 2H20
    You've got 2Cl- on both sides!

    There's no oxidation going on.
 
 
 
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