Formal Charge

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duenezjuleny1D
Posts: 48
Joined: Fri Sep 28, 2018 12:24 am

Formal Charge

Postby duenezjuleny1D » Wed Jul 31, 2019 2:00 am

When making a Lewis structure for an ion, does it matter what atom the formal charge is on, or the structure is valid as long as the overall formal charge is correct?

Ethan McCarthy 1F
Posts: 31
Joined: Wed Feb 27, 2019 12:17 am

Re: Formal Charge

Postby Ethan McCarthy 1F » Wed Jul 31, 2019 7:56 am

I believe the more electronegative atom of the two involved in a bond would be the more likely atom to have the negative formal charge. However, I'm not sure if the opposite is true for the positive formal charges.

Pipiena Malafu 3J
Posts: 39
Joined: Fri Sep 28, 2018 12:27 am

Re: Formal Charge

Postby Pipiena Malafu 3J » Fri Nov 08, 2019 6:09 am

For most stable structures, the more electronegative atom should typically be the one with the negative formal charge and the opposite is true for the opposite case.

VioletKo3F
Posts: 51
Joined: Sat Sep 07, 2019 12:18 am

Re: Formal Charge

Postby VioletKo3F » Fri Nov 08, 2019 9:34 am

What's the equation for the formal charge?

505312292
Posts: 63
Joined: Sat Aug 17, 2019 12:17 am

Re: Formal Charge

Postby 505312292 » Fri Nov 08, 2019 9:44 am

VioletKo3F wrote:What's the equation for the formal charge?

V-(L+S/2) where V is for valence electrons, L is for number of lone electrons, and S is for number of shared electrons.

Nuoya Jiang
Posts: 49
Joined: Sat Sep 14, 2019 12:17 am

Re: Formal Charge

Postby Nuoya Jiang » Fri Nov 08, 2019 10:34 am

After checking the formal charge, we also prefer structures that have -1 on the more electronegative atoms.

emaad_3H
Posts: 51
Joined: Thu Jul 11, 2019 12:17 am

Re: Formal Charge

Postby emaad_3H » Sat Nov 09, 2019 11:06 pm

You want to minimize the magnitude of formal charges for the sum of the atoms. You want to maximize the number of formal charges of 0.

Amanda Mei 1H
Posts: 56
Joined: Sat Aug 24, 2019 12:16 am

Re: Formal Charge

Postby Amanda Mei 1H » Sat Nov 09, 2019 11:24 pm

The most stable Lewis structure for an ion is the one that minimizes formal charges (minimize having separate charges). Also, the negative formal charge should be on the most electronegative atom.

Areena H 3F
Posts: 54
Joined: Wed Dec 05, 2018 12:18 am

Re: Formal Charge

Postby Areena H 3F » Sun Nov 10, 2019 11:44 am

The most electronegative atom has the most negative charge on it, but when we want the lowest energy structure with the least amount of formal charges as possible.

BCaballero_3A
Posts: 44
Joined: Wed Nov 14, 2018 12:22 am

Re: Formal Charge

Postby BCaballero_3A » Sun Nov 10, 2019 4:31 pm

The most electronegative atom should have the negative charge, I think it does matter what the formal charges are on individuals which would then lead to the correct charge for the overall structure.


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