## Formal Charge

derek1d
Posts: 19
Joined: Wed Jun 28, 2017 3:00 am

### Formal Charge

When calculating formal charge, how do we tell apart which electrons are valence from those that are lone or shared? Aren't lone and shared electrons also valence electrons? If not, how can we distinguish them to utilize the formula FC=V-(L+S/2)? Thank you

Davalanya 1F
Posts: 23
Joined: Fri Jun 23, 2017 11:39 am
Been upvoted: 1 time

### Re: Formal Charge

I think in order to calculate formal charge you have to first draw our the Lewis structure so that you can see the lone pairs and the bonds.

Yuting Zhu 3D
Posts: 17
Joined: Tue Oct 10, 2017 7:14 am

### Re: Formal Charge

Yes, lone pairs are definitely valence electrons. However, they do not have bonds, so you don't have to divide them by two. In order to utilize this formula, I believe that you should be able to draw the lewis structure. Hope this helps!

Yashaswi Dis 1K
Posts: 56
Joined: Fri Sep 29, 2017 7:04 am

### Re: Formal Charge

When looking at a lewis structure diagram, there will be lone pair electrons (dots around the element) which you will count each dot as one and then there will also be the single bond lines, which instead of counting as two electrons, count them as one. So add them up and then subtract it from the valence electrons of that element shown on the periodic table.