Resonance
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Resonance
When we have various resonance structures how do we determine which is the most stable/favorable structure? Thanks!
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Re: Resonance
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!
Hope this helps!
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Re: Resonance
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.
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Re: Resonance
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
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.
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Re: Resonance
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
besides what listed above, it's also favorable to have negative formal charges on more electronegative atoms.
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Re: Resonance
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.
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Re: Resonance
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.
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Re: Resonance
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
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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