## Formal charges in charged molecules

$FC=V-(L+\frac{S}{2})$

marcus lin 1E
Posts: 54
Joined: Fri Sep 28, 2018 12:28 am

### Formal charges in charged molecules

How do you determine where the negative formal charge lies in a negatively charged molecule?

Shivangi_2J
Posts: 65
Joined: Fri Sep 28, 2018 12:15 am

### Re: Formal charges in charged molecules

the negative formal charge usually is on the element that is most electronegative

405112316
Posts: 62
Joined: Fri Sep 28, 2018 12:17 am

### Re: Formal charges in charged molecules

There is no difference in process. You still draw all the resonance Lewis structures and use the F = valence - (non bonding electrons - (bonding electrons/2)) equation.

Brian Chang 2H
Posts: 65
Joined: Fri Sep 28, 2018 12:17 am

### Re: Formal charges in charged molecules

Honestly, just balance everything as you normally would and where the formal charge ends up is probably right. There is no hard and fast rule for which element gets the formal charge because it depends how you balance the structure.

Cole Elsner 2J
Posts: 88
Joined: Fri Sep 28, 2018 12:25 am

### Re: Formal charges in charged molecules

Just carry out the process of drawing the lewis structure and finding formal charge. At the end of it all once it's balanced you'll be able to figure it out

Brian Hom 2F
Posts: 60
Joined: Fri Sep 28, 2018 12:24 am

### Re: Formal charges in charged molecules

When I look for formal charges, I usually just subtract the number of valence electrons by the number of bonds and electrons surrounding an atom. You could also use the formula FC=valence-(lone pairs+shared/2).