dentalmagnet

10+ Year Member
Oct 31, 2008
248
0
Status (Visible)
I have the 2007-2008 edition of the Kaplan DAT book. On page, 680 #92. Does anyone else think this question is wrong? The answer they give is E which has carbon with 5 bonds! outrageous right? lol...please if you are good at organic and you have this book sitting in your room, open it and let me know what you think. Thank you so much!!
 

dentalmagnet

10+ Year Member
Oct 31, 2008
248
0
Status (Visible)
Carbon can't have 5 bonds. I have the Kaplan book but not with me right now. I will check later for you

oh yeah..the explanation does not even make sense. They say C is wrong because the carbonyl only has 3 bonds...but in the picture, the carbonyl has four bonds! I just want to see if anyone can show me something I'm not seeing. Thanks Joedat41!
 
About the Ads

dentalmagnet

10+ Year Member
Oct 31, 2008
248
0
Status (Visible)
You're right. Both C-O bonds should really be single bonds.

Did you look in the kaplan book? Did you notice that too? I'm taking it into my organic professor on Monday because it's bothering me. Such a simple question, such a very wrong answer. Carbon never has 5 bonds!!
 

Sublimation

10+ Year Member
5+ Year Member
Jun 14, 2008
574
0
Status (Visible)
  1. Pre-Dental
I have the 2007-2008 edition of the Kaplan DAT book. On page, 680 #92. Does anyone else think this question is wrong? The answer they give is E which has carbon with 5 bonds! outrageous right? lol...please if you are good at organic and you have this book sitting in your room, open it and let me know what you think. Thank you so much!!

That is not a typo. that is correct. Have you ever seen a resonance structure with a combined representation? all they are showing you as that the electrons get delocalized along those bonds. That answer seems perfectly correct to me. Look at it again and draw the lone pairs on the N and draw out the triple bonds in the aromtic ring agian, and you will see that the representation fits perfectly. Chemists usually denote a resonance stabalized bond as such
(check attachment)
 

Attachments

  • EG.doc
    17 KB · Views: 44

Sublimation

10+ Year Member
5+ Year Member
Jun 14, 2008
574
0
Status (Visible)
  1. Pre-Dental
Did you look in the kaplan book? Did you notice that too? I'm taking it into my organic professor on Monday because it's bothering me. Such a simple question, such a very wrong answer. Carbon never has 5 bonds!!

I would agree that the way they chose to represent the "correct" answer was incorrect in itself. there should be only one negative charge on one o fhthe two oxygen atoms. The one with the double bond should be neutral, and if you are using the parameters they are using for representing a delocalized bond, then you will need to draw "six"bonds on the carbon you are referring to. That is one of MANY poorly represented answer choices, i hope the real DAT is not like that. Gluck I will draw out the Correct representation of this molecule for you. I will post it by tomorrow.
 

dentalmagnet

10+ Year Member
Oct 31, 2008
248
0
Status (Visible)
Thank you for your detailed response. I see what you are saying..but I'm not sure that this particular answer means that. I mean, wouldn't they use a dashed line along with the bold line? I see that one bond may be considered shorter than the other..but they drew that for the C-N bond as well. I don't know.
 

zuma35

10+ Year Member
5+ Year Member
Sep 6, 2008
128
0
Status (Visible)
  1. Dental Student
You guys are reading way too much into this. They did not intend any combined representation or anything. It's a simple typo. There should only be a single bond between the C-O.
 
About the Ads
This thread is more than 12 years old.

Your message may be considered spam for the following reasons:

  1. Your new thread title is very short, and likely is unhelpful.
  2. Your reply is very short and likely does not add anything to the thread.
  3. Your reply is very long and likely does not add anything to the thread.
  4. It is very likely that it does not need any further discussion and thus bumping it serves no purpose.
  5. Your message is mostly quotes or spoilers.
  6. Your reply has occurred very quickly after a previous reply and likely does not add anything to the thread.
  7. This thread is locked.