|MadSci Network: Chemistry|
In my OAC-AP (Ontario Academic Credit, Advanced Placement) level chemistry course, we learned that many molecules and ions have more than one Lewis structure, and that we can find the most acceptable model by finding the formal charge of the ions/molecules. We used the model of a sulphate ion to see that the model with two single bonded oxygens and two double bonded oxygens around a central sulphur atom was the most acceptable. However, when we were drawing possible models for the ion, one of my classmates drew the ion as a chain (O-O-S-O-O), and it technically followed the rules for Lewis structures as we have learned them so far. It also has the same formal charge as the proper sulphate ion. Our teacher said that the sulphur ion with the two single and two double bonds is the only one they have found to be possible experimentally, but that he doesn't know why the chain structure doesn't work/isn't possible. Why is it not possible?
Re: What if two Lewis structures for a molecule have the same formal charge?
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