14.5 part a

[Emily Glaser 1F]

How is O3 --> O2 being reduced, according to this question?

If the oxidation charge on the left is -6 and it is going to -4, isn't that oxidation? Am I doing this wrong?

[Ramya Lakkaraju 1B]

I think since the bromine is going from -1 to 5 (meaning it's oxidation), the oxygen would have to be reduced for this to be a redox reaction.

[Sally Nason - 1K]

It will become more obvious that oxygen is being reduced once you balance the hydrogens and oxygens in the equation. The half reaction isn't balanced so it is difficult to tell what is happening. The balanced reaction should look like H2O (l) + O3 (g) + 2e- -> O2 (g) + 2OH- (aq). The oxygen is going from having a neutral charge to a minus 2 charge, as there are 2OH-. This would be why the 2 electrons appear on the left side of the equation.