Are these statements about resonance true?

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SUMMARY

The discussion centers on the validity of two statements regarding resonance structures in chemistry. The first statement, asserting that all contributing resonance structures must have the same net formal charge, is confirmed as true. The second statement, which claims that all atoms in contributing resonance structures must have complete octets, is deemed false, as demonstrated by examples like sulfur in sulfuric acid, which can exceed the octet rule due to its ability to utilize d orbitals for hybridization.

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  • Understanding of resonance structures in chemistry
  • Knowledge of formal charge calculations
  • Familiarity with the octet rule and its exceptions
  • Basic concepts of hybridization, particularly sp3d2
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  • Research the concept of resonance structures in organic chemistry
  • Learn about formal charge and its implications in molecular stability
  • Study exceptions to the octet rule, focusing on elements in periods 3 and above
  • Explore hybridization types, specifically sp3d2 and its applications in molecular geometry
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Chemistry students, educators, and professionals seeking to deepen their understanding of resonance structures and the octet rule in molecular chemistry.

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Homework Statement



Are the following statements true?

1) All contributing resonance structures must have the same net formal charge.
2) All atoms in contributing resonance structures must have complete octets.

The Attempt at a Solution



The first one strikes me as true. Net formal charge is just the overall charge on the molecule. It would not make sense if a resonance structure for a molecule differed in formal charge. Plus resonance structures are made by pushing electrons around, not by taking electrons away.

The second one does not strike me as true; there are many violations of the octet rule as we skip past period 2 on the periodic table. Take sulfuric acid as an example; it forms four bonds, giving the central atom a formal charge of +2. That is a violation of the octet rule; sulfur is in the same column as oxygen and only needs to form two bonds to complete its octet. however it forms four.
 
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Octet rule is something like teaching children about whole numbers. Then later on, you teach them about integers. Octet rule isn't a rule; its scope is limited to Neon.

Your argument on the first one is nothing to argue on.

For the second argument, since Sulphur HAVE d orbitals, it can expand its octet and accommodate additional electrons in those orbitals. It is evident as Sulphur in Sulphuric Acid exhibits sp3d2 hybridization.
 
So I'm right about both?
 
You are to judge yourself. :wink:
 
I'll take that as a yes
 

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