Resonance Structures and Molecular Shape

[Melanie Krahn 1C]

How does molecular shape impact resonance structures? Will resonance structures always have the same shape as one another or are there exceptions?

[dana hu 1B]

hello! no that is not the case. Resonance molecular structure will not always be the same shape.

[Lauren Mungo 1K]

No they will all not necessarily have the same shape. I would assume that you would be asked for the shape of the most stable resonance structure.

[Alan Huang 1E]

It's more so that resonance structures explain molecular shape of a molecule rather than the other way around.

The combination of resonance structures each adds a specific part to the overall resonance hybrid and overall shape of the molecule.

For example, carbonate ion CO3 2- would be predicted to have 2 C-O bonds of one length and a C=O bond of a shorter length.
However, experimentally it's found that all bonds are the same length because of the various resonance structures that add to the hybrid.