AQA 5 - Vanadiam Redox Equilibria

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  1. Shafski's Avatar
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    • Posts: 166
    AQA 5 - Vanadiam Redox Equilibria
    Have this question.. no idea how and why the answer is what it is. Can't find much about it in the book either. Can anyone assist please?


    The "data given in table" mentioned in question is attached


    (c) An excess of acidified potassium manganate(VII) was added to a solution containing V2+(aq) ions. Use the data given in the table to determine the vanadium species present in the solution at the end of this reaction. State the oxidation state of vanadium in this species and write a half-equation for its formation from V2+(aq).
    Vanadium species present at end of reaction ................................ .............................

    Half-equation ................................ ................................ ................................ ..............
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  2. matthew769's Avatar
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    Re: AQA 5 - Vanadiam Redox Equilibria
    (Original post by Shafski)
    Have this question.. no idea how and why the answer is what it is. Can't find much about it in the book either. Can anyone assist please?


    The "data given in table" mentioned in question is attached


    (c) An excess of acidified potassium manganate(VII) was added to a solution containing V2+(aq) ions. Use the data given in the table to determine the vanadium species present in the solution at the end of this reaction. State the oxidation state of vanadium in this species and write a half-equation for its formation from V2+(aq).
    Vanadium species present at end of reaction ................................ .............................

    Half-equation ................................ ................................ ................................ ..............
    The answer is (VO2)+ I think. MnO4 - is the strongest oxidising agent in that table so when V 2+ is oxidised to V 3+, the V 3+ formed can then be oxidised to (VO)2+, which can then also be oxidised to (VO2)+
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