The Oxygen in HOCOO-: Does it Participate in Resonance?

[MathewsMD]

For the molecule HOCOO-, does the oxygen in the OH group participate in resonance? Is that particular contributing structure a major contributor to the hybrid structure?

After a bit of discussion with peers, we agree the oxygen has electron-withdrawign effects, but since it is already bonded to a hydrogen, adding electrons to the oxygen would disrupt its current bond (i.e. too many electrons would destabilize the atom). Is there any support for the oxygen in the OH either participating or not participating in resonance? If so, do you mind providing an explanation? Thank you!

 

[Ygggdrasil]

You can certainly draw resonance structures where the oxygen in the OH group contains a double bond to the central carbon. However, you should also consider whether that resonance structure is an important contributor to the overall resonance hybrid. What factors do you know that help you determine which resonance structures are the most important to consider? (if you don't know, here's a good place to start: http://www.chem.ucla.edu/harding/tutorials/resonance/imp_res_str.html). What does this tell you about that particular resonance structure in comparison to the other resonance structures for HOCOO–?