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Most stable resonance

Discussion in 'DAT Discussions' started by Awuah29, Apr 24, 2007.

  1. Awuah29

    Awuah29 Christian predent

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    So, this is another problem I struggle with. Which is the most stable resonance and why? Is the answer here D, because the ring has all the pi bonds ?
    thanks
     

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  3. Lonely Sol

    Lonely Sol cowgoesmoo fan!

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    The most stable resonance structure is A since it all carbons meet the octet rule.

    Let me know if you want to know why all the other ones are not as stable!
     
  4. Awuah29

    Awuah29 Christian predent

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    ok, I see Lonely Sol, what about the other ones ?
    So basically if they ask for most stable resonance look out for cmpd that obeys the octet
    thanks
     
  5. Lonely Sol

    Lonely Sol cowgoesmoo fan!

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    Yes, most of the time, if it meets the octet rule then it is also the most stable seonance structure.
     
  6. DailyDrivenTJ

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    Stabilities are achieved by octet, stronger bonds, and negative charges on the electronegative atoms.

    For this case, anions are formed on the oxygen and oxygen is the most electronegative atom in this example thus can stabilize the anion better than the carbons. So the answer is A like lonlysol said.
     
  7. Streetwolf

    Streetwolf Ultra Senior Member
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    Here's good advice for when you take the test... look to eliminate the easy ones first. Choice D is easy to eliminate since the carbon atom on the top has 5 bonds. Carbon will NEVER EVER EVER EVER EVER have 5 bonds and be stable. Even though the problem may look difficult there are definitely some choices which are 100% wrong because of easy concepts you've learned. Learn to pick up on these obvious wrong answers and you will be smooth sailing!
     
  8. jdmsamurai

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    Be has 2 bonds, B has 3 bonds, P, S and any thing after can have more than 4 bonds due to the d orbitals
     
  9. infernobutterfl

    infernobutterfl Pyro user

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    Actually, funny thing is the most stable resonance would be the structure they gave you in the question. Of the remainder answer choices, A is the most stable.
     
  10. DailyDrivenTJ

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    you do have a point there.
     
  11. gym.addict

    gym.addict ain't nuttin but a peanut

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    Also besides whats already been said about octet rule and EN atoms, if you try pushing arrows for some of those structures you can't even get to some of em...like some just lose bonds out of nowhere on those answers
     
  12. Awuah29

    Awuah29 Christian predent

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    thanks everyone for your help , you guys are awesome :thumbup:
     

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