Is Option 2 the Correct Answer for Huckel's Law?

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Discussion Overview

The discussion revolves around Huckel's Law and its application to determine the aromaticity of different molecular options based on the number of pi electrons. Participants are analyzing various options to see which satisfies the criteria for aromaticity according to the law.

Discussion Character

  • Homework-related
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant questions the meaning of the dash and two dots in the brackets, wondering if they represent lone pair electrons and how this affects the count of pi electrons.
  • Another participant expresses uncertainty about which electrons should be considered when applying Huckel's rule, specifically asking if option 1 has only 4 electrons involved in resonance.
  • Some participants assert that Huckel's rule pertains only to pi electrons, raising questions about whether all electrons in resonating structures should be included.
  • A participant prompts others to consider if they have accounted for all pi electrons in their calculations.
  • It is noted that both option 1 and option 3 yield 6 pi electrons, suggesting that both could be aromatic.
  • Concerns are raised about the validity of option 3 as a possible structure, with a suggestion to count the number of electrons on each carbon to verify its feasibility.

Areas of Agreement / Disagreement

Participants express differing views on which options are aromatic, with some suggesting that multiple options may satisfy Huckel's criteria. The discussion remains unresolved regarding the correct interpretation of the options and the application of Huckel's Law.

Contextual Notes

There are limitations regarding the assumptions made about which electrons are considered in the context of Huckel's Law, and the discussion does not resolve the mathematical steps involved in determining aromaticity for each option.

Priyadarshini
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Homework Statement

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Homework Equations


Huckel's Law: 4n+2=pi electrons

The Attempt at a Solution


I'm not sure what the dash and two dots in the brackets mean, are those lone pair of electrons?
Not including them as pi electrons:
option 1: 4= 4n+2
n=1/2, so no aromatic
option 2: 2= 4n+2
n= 0, so aromatic
option 3: 4=4n+2, n=1/2
so the answer should be option 2?
 
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I don't know if you were told which electrons to consider when you take the value of n in huckels rule
Does option 1 have just 4 electrons involved in the resonance?
 
Suraj M said:
I don't know if you were told which electrons to consider when you take the value of n in huckels rule
Does option 1 have just 4 electrons involved in the resonance?
Doesn't Huckels rule involve pi electrons only? Does it involve all the electrons taking part in the resonating structures?
 
Do you think you've considered ALL the pi electrons?
 
Suraj M said:
Do you think you've considered ALL the pi electrons?
Oh, but then both option 1 and 3 work out to be aromatic as both have 6 pi electrons.
 
Is option 3 even a possible structure? Just look at it
Count the number of electrons on each carbon!
 
Suraj M said:
Is option 3 even a possible structure? Just look at it
Count the number of electrons on each carbon!
Ah, I see! Thanks.
 

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