Redox equation under acidic conditions?

C6H8O6 + CrO4^2- -> C6H6O6 + Cr3+

can we balance this equation?

what is the oxidation number of Cr in CrO4 2- and Cr3+?

which one oxidizes and reduced?

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  • 1 month ago
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    half-reactions:

    C6H8O6 ---> C6H6O6

    CrO4^2-  ---> Cr3+

    balance:

    C6H8O6 ---> C6H6O6 + 2H^+ + 2e^-3e^- + 8H^+ + CrO4^2-  ---> Cr^3+ + 4H2O

    equalize electrons:

    3C6H8O6 ---> 3C6H6O6 + 6H^+ + 6e^-6e^- + 16H^+ + 2CrO4^2-  ---> 2Cr^3+ + 8H2O

    add:

    10H^+ + 3C6H8O6 + 2CrO4^2-  ---> 2Cr^3+ + 3C6H6O6 + 8H2O

    ----------------

    CrO4 2- ---> 6+

    Cr3+ ---> 3+

    ----------------

    which one oxidizes and reduced?

    The chromate is reduced. It is called the oxidizing agent.

    The carbon in the C6H8O6 was oxidized. It is the reducing agent.

    The Cr3+ is the result of the chromate being reduced. It is not called anything in particular. Only the reactants are addressed with the above terms I used.

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