ΔG∘=−nFE∘
Mn+2+2e−→Mn ........... (1)
ΔG=−2×F×(−1.18)=+2.36 F
2Mn+3+2e−→2Mn+2 ....... (2)
ΔG=−2×F×(+1.51)=−3.02 F
(1) - (2)
3Mn+2→Mn+2Mn+3
ΔG=+2.36F+(3.02F)=5.38 F
ΔG=−2×F×E
E=−2×F5.38F=−2.69 V
We know that when Ecell < 0, cell is non-spontaneous.
JEE Main 2014 — Chemistry Physical Chemistry
Given below are the half - cell reactions :
Mn2++2e−→Mn;2(Mn3++e−→Mn2+);E∘=−1.18 VE∘=+1.51 V
The E∘ for 3Mn2+→Mn+2Mn3+ will be :
Held on 6 Apr 2014 · Verified 6 Jul 2026.
−2.69 V ; the reaction will not occur
−2.69 V ; the reaction will occur
−0.33 V ; the reaction will not occur
−0.33 V ; the reaction will occur
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