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Did I summarize the octet rule exception correctly?

Posted: Tue Nov 05, 2019 7:22 pm
by Prasanna Padmanabham 4I
So basically, when drawing Lewis Structures, the first goal should be to get the smallest formal charge for all the atoms. Does this mean that I should give double bonds to structures even if it means breaking the octet rule if it means that all the atoms in the molecule will have a formal charge of 0 (of course I would break the octet rule for atoms in the 3rd row or below)?

Thank you!

Re: Did I summarize the octet rule exception correctly?

Posted: Tue Nov 05, 2019 7:30 pm
by Baoying Li 1B
Yes, I think your summary is pretty good. Just be aware that the formal charge is not always equal to zero, but the more close to zero, the more stable the structure is. Elements like P, As, Cl, As and etc. usually break the octet rule because of their odd valence electrons. Lastly, make sure the total number of valence electron of the Lewis structure is correct. Good luck with the Midterm!