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Hydrogen electrode with Fe3+/Fe2+ cell at 0.712 V: ratio of Fe2+ to Fe3+

The same question, asked 2 times: 25 Jan 2023*, 30 Jan 2023. Every wording below, oldest first.

Try each one first, then open its answer.

  1. Question 1

    25 Jan 2023

    58
    Consider the cell
    Pt(s)∣H2( g)(1 atm)∣H+(aq,[H+]=1)∥Fe3+(aq),Fe2+(aq)∣Pt(s)Pt(s)\left| H_{2}(\text{ }g)(1\text{ }atm) \right|H^{+}\left( aq,\left\lbrack H^{+} \right\rbrack= 1 \right)\parallel Fe^{3 +}(aq),Fe^{2 +}(aq) \mid Pt(s)
    Given EFe3+/Fe2+o=0.771 VE_{Fe^{3 +}/Fe^{2 +}}^{o}= 0.771\text{ }V and EH+/12H20=0 V,T=298 KE_{H^{+}/\frac{1}{2}H_{2}}^{0}= 0\ V,T = 298\text{ }K If the potential of the cell is 0.712 V0.712\text{ }V, the ratio of concentration of Fe2+Fe^{2 +} to Fe3+Fe^{3 +} is (Nearest integer)
  2. Question 2

    30 Jan 2023

    53
    Consider the cell
    Pt(s)∣H2( g,1 atm)∣H+(aq,1M)∣∣Fe3+(aq),Fe2+(aq)∣Pt(s)Pt_{(s)}\left| H_{2}(\text{ }g,1\text{ }atm) \right|H^{+}(aq,1M)||Fe^{3 +}(aq),Fe^{2 +}(aq) \mid Pt(s)
    When the potential of the cell is 0.712 V0.712\text{ }V at 298 K298\text{ }K, the ratio [Fe2+]/[Fe3+]\left\lbrack Fe^{2 +} \right\rbrack/\left\lbrack Fe^{3 +} \right\rbrack is (Nearest integer) Given: Fe3++e−=Fe2+,EθFe3+,Fe2+∣Pt=0.771Fe^{3 +}+e^{-}=Fe^{2 +},E^{\theta}Fe^{3 +},Fe^{2 +}\mid Pt = 0.771
    2.303RTF=0.06 V\frac{2.303RT}{F}= 0.06\text{ }V