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Kaili Valenzuela 2B
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Postby Kaili Valenzuela 2B » Sun Nov 15, 2020 11:49 am

When we have various resonance structures how do we determine which is the most stable/favorable structure? Thanks!

Stuti Pradhan 2J
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Re: Resonance

Postby Stuti Pradhan 2J » Sun Nov 15, 2020 12:09 pm

To find the most favorable resonance structure you should look at the formal charge on all the atoms. A compound where each atom has a formal charge of 0 is the most stable and therefore will contribute the most to the resonance structure. Other things to look out for is that you do not want highly electronegative atoms to have a positive formal charge and you do not want the central atom to have a formal charge if possible (as these are less stable versions of the molecule). Basically, the least amount of formal charge and the least amount of separation of charges (just 2 atoms having a formal charge instead of 4, for example) will lead to the most favorable structure that will be represented the most in the actual structure.

Hope this helps!

Nathan Tong 3G
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Re: Resonance

Postby Nathan Tong 3G » Sun Nov 15, 2020 2:31 pm

Another thing to consider besides the ones listed above, is that it is not favorable to have two atoms next to each other with the same sign charge, such as two adjacent atoms with a +1 charge. It is more favorable to have adjacent atoms with a + and - charge.

Luveia Pangilinan 1A
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Re: Resonance

Postby Luveia Pangilinan 1A » Sun Nov 15, 2020 2:34 pm

You would have to look at the overall formal charge, if it's 0 it is the most ideal and most stable. You would also have to look at the central atom's charge :D. I think Stuti stated it well.

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Re: Resonance

Postby Armen_Isayan_2L » Sun Nov 15, 2020 3:47 pm

Hello! In order to determine the most stable structure among various resonance structures, it is crucial to find the resonance structure with the least amount of charges. This will indicate how stable it is in reality. Also within the structure, the most electronegative atoms will have negative charges and the lesser electronegative atoms will have positive charges.

Chudi Onyedika 3A
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Re: Resonance

Postby Chudi Onyedika 3A » Sun Nov 15, 2020 3:59 pm

Ideally, you would want each atom to have no charge. If there are charges, then you should select the structure that has the least amount. You should also select the structure that has negative charges on the electronegative atoms.

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Re: Resonance

Postby joshtully » Sun Nov 15, 2020 9:29 pm

The most stable resonance structure has to little to no charges on each atom.

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Re: Resonance

Postby Nan_Guan_1L » Sun Nov 15, 2020 10:17 pm

besides what listed above, it's also favorable to have negative formal charges on more electronegative atoms.

Namratha Gujje
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Re: Resonance

Postby Namratha Gujje » Sun Nov 15, 2020 10:19 pm

The most favorable structure can be determined by the formal charge of each atom of the structure. We would want as much atoms as possible to have a formal charge of zero.

Ellison Gonzales 1H
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Re: Resonance

Postby Ellison Gonzales 1H » Sun Nov 15, 2020 11:04 pm

The most stable structure correlates with the atoms’ formal charges in the structure. Also make a note that if the chemical compound has a charge, it is best if the most electronegative atom has that negative charge on it. Typically, the best structure will have the least electronegative atom at the center.

Heidi Buri 2I
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Re: Resonance

Postby Heidi Buri 2I » Mon Nov 16, 2020 4:05 pm

Hi! To determine which resonance structure is the most stable/favorable, you must look at the covalent bonds in the structure, the formal charge, and the separation of formal charge. Resonance stuctures with more covalent bonds, the least number of formal charges, and with the least separation of formal charge are more stable.

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Re: Resonance

Postby Cooper_Geralds_3B » Mon Nov 16, 2020 4:16 pm

Hi! Generally the resonance structure with a formal charge closest to zero is the most stable structure! Try to see if the charges on each atom cancel each other out, and if they do, this is a good indicator that the formal charge is zero and the structure is stable!

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