For `Cr_(2)O_(7)^(2-)+14H^(+)+6e^(-)to2Cr^(3+)+7H_(2)O,E^(@)=1.33V` At `[Cr_(2)O_(7)^(2-)]=4.5` millimole, `[Cr^(3+)]=15` millimole, E is 1.067V. Calculate the pH of the solution.

For `Cr_(2)O_(7)^(2-)+14H^(+)+6e^(-)to2Cr^(3+)+7H_(2)O,E^(@)=1.33V` At

1.	For `Cr_(2)O_(7)^(2-)+14H^(+)+6e^(-)to2Cr^(3+)+7H_(2)O,E^(@)=1.33V` At `[Cr_(2)O_(7)^(2-)]=4.5` millimole, `[Cr^(3+)]=15` millimole, E is 1.067V. Calculate the pH of the solution.
Answer» For the given reaction, `Cr_(2)O_(7)^(2-)+14H^(+)+6e^(-)to2Cr^(3+)+7H_(2)O` `E=E^(@)=-(0.0591)/(6)"log"([Cr^(3+)]^(2)[H_(2)O]^(7))/([Cr_(2)O_(7)^(2-)][H^(+)]^(14))` `1.067=1.33-9.85xx10^(-3)"log"([15xx10^(-3)]^(2)[1]^(7))/([4.5xx10^(-3)][H^(+)]^(14))` `(-0.263)/(-9.85xx10^(-3))=2log(15xx10^(-3))-log(4.5xx10^(-3))-14log(H^(+))` `26.7=2(-1.82)+2.34+14pH` or `pH=(28)/(14)=2`.

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For `Cr_(2)O_(7)^(2-)+14H^(+)+6e^(-)to2Cr^(3+)+7H_(2)O,E^(@)=1.33V` At `[Cr_(2)O_(7)^(2-)]=4.5` millimole, `[Cr^(3+)]=15` millimole, E is 1.067V. Calculate the pH of the solution.

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