homework question 6L.9

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Jade Hinds 2B
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homework question 6L.9

Postby Jade Hinds 2B » Mon Feb 24, 2020 9:51 pm

(a) write balanced half-reactions for the redox reactions of an acidified solution of potassium permanganate and iron (II) chloride. (b) write the balanced equation for the cell reaction and devise a galvanic cell to study the reaction.

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Re: homework question 6L.9

Postby nicole-2B » Tue Feb 25, 2020 8:29 pm

a) MnO4-(aq) +8H+(aq)+5e- yields Mn2+(aq) +4H2O (cathode half reaction)
5[Fe2+ (aq) yields Fe3+(aq)+e-] anode half reaction
Two equations together:
MnO4-(aq)+fFe2+(aq)+8H+(aq) yields Mn2+(aq) + Fe3+(aq) +4H20(l)

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Re: homework question 6L.9

Postby 805303639 » Thu Feb 27, 2020 8:17 pm

The balanced redox reaction should be: MnO4-(aq) + 5Fe^2+(aq) + 8 H+(aq) --> Mn^2+(aq) + 5Fe^3+(aq) + 4H2O(l).
As for the galvanic cell, we know our cathode and our anode from the balanced half-reactions:
nicole-2B wrote:a) MnO4-(aq) +8H+(aq)+5e- yields Mn2+(aq) +4H2O (cathode half reaction)
5[Fe2+ (aq) yields Fe3+(aq)+e-] (anode half reaction)

Since neither half-reaction involves a species in its solid state, include a platinum electrode (Pt) in each half-cell. Separate species in the same phase by commas and exclude H2O(l):
Pt(s)|Fe^2+(aq), Fe^3+(aq)||MnO4-(aq), H+(aq), Mn^2+(aq)|Pt(s)

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