Ek Chemistry 954: Strongest reducing agent from Half-Reactions?

[Jack08]

Based only on the half-reactions in the table, which of the following is the strongest reducing agent?

A) Cd2+ E= -0.40
B) F- E= -2.87
C) I- E= -0.54
D) Na+ E= -2.71


First off, I realize A and D cannot be further oxidized, so it's down to B and C. I chose B as it was a more negative number (F- = -2.87) while I- was only -0.54. However, the correct answer is C (I- E= -0.54)

can someone explain to me why this is? Thanks

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[Jack08]

bumperoooski....

 

[onedirection]

It's because the reactions they give

2F- --> F2 + 2e-
and
2I- --> I2 + 2e-

are oxidizing potentials and not reduction potentials [F- and i- are getting oxidized in theses reactions]

The I- one is more positive therefore it is the stronger reducing agent as it's more readily oxidized