Drawing resonance

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305117729
Posts: 30
Joined: Fri Sep 28, 2018 12:16 am

Drawing resonance

Postby 305117729 » Sun Nov 11, 2018 2:10 pm

When we are drawing lewis structure of one molecule, should we always draw all resonance of this molecule?

Samantha Hoegl Roy 2C
Posts: 81
Joined: Fri Sep 28, 2018 12:15 am

Re: Drawing resonance

Postby Samantha Hoegl Roy 2C » Sun Nov 11, 2018 2:14 pm

if there is resonance, yes. You have to show that you know there are 3 different structures for the same molecule. if you only draw one, one could assume you believe one bond is shorter than the others

Connie Chen 3D
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Joined: Mon Jan 08, 2018 8:12 am

Re: Drawing resonance

Postby Connie Chen 3D » Sun Nov 11, 2018 2:45 pm

Yes, it is necessary to draw all the resonance structures in order to show that the overall bonds of the molecule are equal, not one greater than the other.

Karina Jiayu Xu 4E
Posts: 58
Joined: Fri Sep 28, 2018 12:29 am

Re: Drawing resonance

Postby Karina Jiayu Xu 4E » Sun Nov 11, 2018 9:53 pm

Wait how do you know if there will be resonance structures on a molecule?

Sheridan Slaterbeck 1J
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Joined: Fri Sep 28, 2018 12:27 am

Re: Drawing resonance

Postby Sheridan Slaterbeck 1J » Sun Nov 11, 2018 10:07 pm

One of the TA's said we are not able to tell yet if a structure has resonance, we will learn that later. We will be told when to draw resonance structures as of now.

Alexandra Ortega 4D
Posts: 31
Joined: Wed Oct 03, 2018 12:17 am

Re: Drawing resonance

Postby Alexandra Ortega 4D » Sun Nov 11, 2018 10:19 pm

I believe we should draw all resonance structures for molecules to show our understanding that lewis structures can have multiple bonds on different equivalent locations and that the actual molecule is a blend or average of all resonance structures.

Ruiting Jia 4D
Posts: 65
Joined: Fri Sep 28, 2018 12:27 am

Re: Drawing resonance

Postby Ruiting Jia 4D » Sun Nov 11, 2018 10:57 pm

If the problem itself does not indicate that we have to draw all the different resonance structures, I believe it is not needed.

Anjali 4A
Posts: 59
Joined: Fri Sep 28, 2018 12:28 am

Re: Drawing resonance

Postby Anjali 4A » Sun Nov 11, 2018 11:19 pm

In a exam/test situation, I think that it'll be safer to draw the resonance structure of the molecule.

Sophia Fox 4B
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Joined: Fri Sep 28, 2018 12:27 am

Re: Drawing resonance

Postby Sophia Fox 4B » Mon Nov 12, 2018 4:25 pm

Yes draw all resonance structures and then double sided arrows between them indicating that there is resonance.

Matthew Choi 2H
Posts: 59
Joined: Fri Sep 28, 2018 12:18 am

Re: Drawing resonance

Postby Matthew Choi 2H » Tue Nov 13, 2018 12:51 am

My TA said that sometimes the problem won't ask you to draw all of the possible resonance structures even if there are multiple resonance structures. This is because (1) they might not want to give away the fact that there are resonance structures in the specific problem or (2) they aren't asking for them. Either way, you should draw all the resonance structures and indicate them with double-sided arrows.

Ethan Breaux 2F
Posts: 63
Joined: Sat Sep 29, 2018 12:16 am

Re: Drawing resonance

Postby Ethan Breaux 2F » Tue Nov 13, 2018 1:59 am

If the bond can go anywhere then might as well draw the arrows I don't think it would ever hurt you.

Erin Nash - 4G
Posts: 29
Joined: Fri Sep 28, 2018 12:27 am

Re: Drawing resonance

Postby Erin Nash - 4G » Tue Nov 13, 2018 9:49 am

You should always draw the resonance structures because the true structure of the molecule is a mixture of all of the resonance structures.

kimberlyrose1G
Posts: 44
Joined: Fri Sep 28, 2018 12:27 am

Re: Drawing resonance

Postby kimberlyrose1G » Sun Nov 18, 2018 4:31 pm

you should draw all of the resonance structures as the true structure will be an average of them all (so by drawing all of them, you show that you know that it can be any of the structures, but is an average in reality)

SophiaKohlhoff4B
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Joined: Fri Sep 28, 2018 12:16 am

Re: Drawing resonance

Postby SophiaKohlhoff4B » Sun Nov 18, 2018 11:17 pm

It is important to draw the resonance for a molecule because it demonstrates that the actual bond lengths are the average of the bond lengths.

danicatran4
Posts: 35
Joined: Fri Sep 28, 2018 12:17 am

Re: Drawing resonance

Postby danicatran4 » Sun Nov 18, 2018 11:59 pm

SophiaKohlhoff4B wrote:It is important to draw the resonance for a molecule because it demonstrates that the actual bond lengths are the average of the bond lengths.

Do we need to include something to show the bond lengths are an average and the same or is that implied when we draw the resonance structures?

505211599
Posts: 60
Joined: Fri Sep 28, 2018 12:28 am

Re: Drawing resonance

Postby 505211599 » Mon Nov 19, 2018 12:25 am

I think that if a lewis structure has resonance, it would be safe to draw out all possible resonance structures.

SophiaKohlhoff4B
Posts: 30
Joined: Fri Sep 28, 2018 12:16 am

Re: Drawing resonance

Postby SophiaKohlhoff4B » Sun Nov 25, 2018 5:31 pm

danicatran4 wrote:
SophiaKohlhoff4B wrote:It is important to draw the resonance for a molecule because it demonstrates that the actual bond lengths are the average of the bond lengths.

Do we need to include something to show the bond lengths are an average and the same or is that implied when we draw the resonance structures?


I don't think you need to include anything to show the bond lengths are an average, however it is important to understand in case a question is specifically asked about the actual bond lengths.

Elizabeth Kim 4E
Posts: 60
Joined: Fri Sep 28, 2018 12:29 am

Re: Drawing resonance

Postby Elizabeth Kim 4E » Thu Nov 29, 2018 2:00 am

Even if it isn't required to draw all of the resonance structures, it's probably helpful in the long run to just draw them all out on tests and homework.


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