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When to calculate formal charge

Posted: Sun Nov 03, 2019 12:31 am
Do you always have to compute formal charge when drawing Lewis structures?

Re: When to calculate formal charge

Posted: Sun Nov 03, 2019 12:59 am
I believe that at this level we would need to account for formal charge as we draw Lewis Structures, as formal charge allows us to determine which Lewis structure is the most correct one.

Re: When to calculate formal charge

Posted: Sun Nov 03, 2019 1:05 am
I don't think you would have to calculate formal charge all the time, I think it would just be when it is being asked for in a problem. Another instance where you most likely will have to calculate it might be when you have to adjust the lewis structure so that all the atoms are stable at a formal charge of 0. Even with that, I think if we are given a problem, it would be stated clearly if they want us to find the formal charge of something.

Re: When to calculate formal charge

Posted: Sun Nov 03, 2019 1:12 am
It would take a lot of time to do formal charge for each lewis structures. It would be best to do them when there are two or more possible structures for one molecule, and you do not know which one is the most favorable one.

Re: When to calculate formal charge

Posted: Sun Nov 03, 2019 1:58 am
When determining the most stable structure do you choose the Lewis structure with the least formal charges on each atom?

Re: When to calculate formal charge

Posted: Sun Nov 03, 2019 1:02 am
Debora Fernandez Clemente_ 4H wrote:When determining the most stable structure do you choose the Lewis structure with the least formal charges on each atom?
Yes that is correct. Hope this helps! :)

Re: When to calculate formal charge

Posted: Sun Nov 03, 2019 10:07 am
Yes, you would want to get the FC as close to zero as possible to get the most stable Lewis structure.

Re: When to calculate formal charge

Posted: Sun Nov 03, 2019 7:52 pm
I do not think it is absolutely necessary every time, but it is a good way to check that the lewis structure is the best possible for the molecule.