[supinemagpie]

Say you have a molecule like aldehyde:

Is it valid to think about a resonance form where the pi electrons in the double bond go completely to the oxygen, leaving the carbon a carbocation and forming a zwitterion. I know this would be a highly unfavored resonance structure, but would the fact that this resonance structure exists contribute to increased the acidity of the carbon in aldehyde?

[pgk]

Please, do not confuse electrophilicity/ nucleophilicity with acidity/ basicity. Otherwise, serious misunderstoods may arise.
Indicatively, Pearson’s HSAB theory mainly refers to electrophilicity/ nucleophilicity and not to “pure” acidity/ basicity.
Besides, Brønsted-Lowry refers to chemical compounds as chemical entities and not to their resonance structures.