In which of the following molecules would you expect the oxygen-to-oxygen bond to be the shortest: H2O2, O2, O3?

I would've assumed O3, because to make the formal charge on the middle Oxygen zero, there is TWO double bonds made between them, but the answer is O2. Why is this? Is it because it only has one double bond? Please help!

Question

In which of the following molecules would you expect the oxygen-to-oxygen bond to be the shortest: H2O2, O2, O3?

I would've assumed O3, because to make the formal charge on the middle Oxygen zero, there is TWO double bonds made between them, but the answer is O2. Why is this? Is it because it only has one double bond? Please help!

whpalmer4 · Answer

My guess is the fact that ozone is a resonance hybrid leads to it having the slightly longer bond.

O dbl O sin O (with 2 non-bonding electrons on middle O)
O sin O dbl O (with 2 non-bonding electrons on middle O)
O sin O sin O  (with 4 non-bonding electrons on middle O)