Question

Could you please answer this?

The reaction of Cr3+(aq) and Cr(s) to form Cr2+(aq). [The reduction potential of Cr2+(aq)to Cr(s) is -0.91 V.]

Calculate ΔG∘rxn.

Calculate K

Answer 1

Cr^3+(aq) + Cr(s) ---------------------> Cr^2+ (aq)

Cr(s) ----------------------> Cr^2+ (aq) + 2e^+    E0 = 0.91v

2Cr^3+ (aq) + 2e^- -----------> 2Cr^2+ (aq)    E0 = -0.407v

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2Cr^3+(aq) + Cr(s) ---------------------> 3Cr^2+ (aq)    Ecell = 0.503v

   n = 2

G⁰     = -nE0cell *F

             = -2*0.503*96500

             = -97079J

G⁰     = -RTlnK

-97079    = -8.314*298*2.303logK

-97079   = -5705.8483logK

logK        = -97079/-5705.8483

logK       = 17

    K        = 10^17 = 1*10^17 >>>>answer