formal charge vs. octet

$FC=V-(L+\frac{S}{2})$

404768057
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formal charge vs. octet

When do we know when finding the formal charge is more important than using the octet rule?

Chem_Mod
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Re: formal charge vs. octet

Octet rule must be obeyed unless an atom has a d subshell available allowing for an expanded octet. Common examples of atoms that can expand their octet are sulfur and phosphorous. An example of an atom that must always obey the octet rule is carbon. It must have 4 bonds.

Beza Ayalew 1I
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Re: formal charge vs. octet

I read silicon and chlorine can also have an expanded octet as well

Amir Akhavan 1E
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Joined: Fri Apr 06, 2018 10:01 am

Re: formal charge vs. octet

The octet rule must always be obeyed unless the atom has extra electrons which can be used from the d and f subshells. However you use the formal charge to help determine the correct lewis structure because the lower the formal charge the more stable it is.