December 01, 2020, 10:16:37 PM
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Topic: Why can't we form this resonance?  (Read 245 times)

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Offline bishiw

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Why can't we form this resonance?
« on: November 14, 2020, 12:50:15 AM »
Why isn't this a viable resonance structure?

Offline AWK

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Re: Why can't we form this resonance?
« Reply #1 on: November 14, 2020, 02:54:45 AM »
What is the definition of a mesomeric structure?
Does the structure you draw meet the definition requirements?
AWK

Offline Babcock_Hall

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Re: Why can't we form this resonance?
« Reply #2 on: November 14, 2020, 08:40:45 AM »
What you drew breaks at least one fundamental principle.

Offline bishiw

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Re: Why can't we form this resonance?
« Reply #3 on: November 14, 2020, 09:46:44 AM »
What you drew breaks at least one fundamental principle.

Which one? I'm completely lost haha. I also meant to draw an oxygen with a + charge, not -.
« Last Edit: November 14, 2020, 10:27:06 AM by bishiw »

Offline bishiw

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Re: Why can't we form this resonance?
« Reply #4 on: November 14, 2020, 10:26:49 AM »
What is the definition of a mesomeric structure?
Does the structure you draw meet the definition requirements?

I meant to draw an oxygen with a + charge instead. Is that still incorrect?

Offline Babcock_Hall

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Re: Why can't we form this resonance?
« Reply #5 on: November 14, 2020, 10:33:31 AM »
It is not a significant contributor to the overall structure.  I suggest thinking about AWK's response.

Offline NDW

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Re: Why can't we form this resonance?
« Reply #6 on: November 17, 2020, 10:36:54 PM »
With the + on the oxygen, your charges are balanced. Given the question, it looks like you are too early in your chemistry study to know that a + on an oxygen and a - on a carbon would be very unstable. It's a good question. When drawing resonance structures, avoid creating point charges and breaking electronegativity rules.

Your revised answer follows the rules, but to a more experience chemist it's a bizzare or "wrong" structure.

http://www.chem.ucalgary.ca/courses/350/Carey5th/Ch01/ch1-7.html

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