Question

Write the reduction half reaction for the redox reaction below.

ClO-(aq) + I-(aq) => Cl-(aq) + I2(s)

Is I- being reduced since Cl is losing an O?

Answer 1

No, its being oxidized. It has a lower reduction potential.

These are the half reactions from a standard half reaction chart:

I2 + 2e- -> 2I-

ClO- + 2e- -> Cl-

**I2 is being oxidized, so you need to reverse the reaction:

2I^- <- - -> I2 + 2e

ClO- + 2e- -> Cl-


Electrons are balanced.

Answer 2

Ok I had the wrong idea, thanks so much!

Answer 3

I posted an answer/solution to another problem that you had. I think that it explains the concept of what you are suppose to be doing a little bit better, or it can be used as an additional resource to help you with similar problems.

Answer 4

I would like to add here that you had the right idea if you had followed through. Your statement that ClO is losing O is ok but since it is LOSING O is must be reduced. Gaining O is oxidation. Of course if O is nowhere in the oxidation it's tough to use that as a definition which is why you should stick to the definition that oxidation is the loss of electrons and reduction is the gain of electrons. Note that Cl is +1 oxidation state and Cl^- is -1 so the Cl has gained two electrons which makes it reduced.