Question

Question #57f70

Answer 1

A Standard Reduction Potential table should have the electrode potentials listed top to bottom from most negative to most positive.

(http://hyperphysics.phy-astr.gsu.edu/hbase/tables/electpot.html)

When this is the case, `Zn_((s))` is actually above `Cu^(2+)` in the table, since it has a more negative standard electrode potential.

The more negative an electrode potential is, the stronger a reducing agent will be. Likewise, the more positive an electrode potential is, the stronger an oxidizing agent will be.

`Zn_((aq))^(2+) + 2e^(-) -> Zn_((s))`, `E^0 = "-0.76 V"`

`Cu_((aq))^(2+) + 2e^(-) -> Cu_((s))`, `E^0 = "+0.16 V"`

A more negative electrode potential means is that `Zn_((s))` can reduce `Cu^(2+)`, or, In other words, a more positive potential means that `Cu_((aq))^(2+)` can oxidize `Zn_((s))`.

Simply put, `Cu^(2+)` is being reduced by `Zn_((s))`.

Check out these answers for a more detailed explanation on how standard electrode potentials work:

http://socratic.org/questions/please-let-me-know-which-is-one-of-the-following-reagents-is-capable-of-transfor

http://socratic.org/questions/i-do-not-know-how-i-can-use-standard-electrode-potentials-decide-which-of-the-fo-1