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Question
What is the half-reaction that occurs at the cathode during electrolysis of an aqueous potassium iodide solution?
| Reduction Half-Reaction | Eº(V) |
K+(aq) + e- K(s) | -2.93 |
| Mg2+(aq) + 2e- Mg(s) | -2.37 |
| 2H2O(l) + 2e- H2(g) + 2OH-(aq) | -0.83 |
| 2H+(aq) + 2e- H2(g) | 0.00 |
| I2(s) + 2e- 2I-(aq) | 0.54 |
| O2(g) + 4H+(aq) + 4e- 2H2O(l) | 1.23 |
A) H2O(l) → O2(g) + 2H+(aq) + 2e-
B) 2H2O(l) + 2e-→H2(g) + 2OH-(aq)
C) K(s) → K+(aq) + e-
D) K+(aq) + e-→K(s)
E) I2(aq) + 2e-→2I-(aq)
Answer
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