## Alternative version of formula

105002507
Posts: 30
Joined: Fri Sep 28, 2018 12:15 am

### Alternative version of formula

Does the formula...

FC = group # - (bonds + nonbinding e-)

work the same as the one presented in lecture? This formula makes more sense to me and seems to result in all the same results.

305113590
Posts: 66
Joined: Fri Sep 28, 2018 12:28 am

### Re: Alternative version of formula

Yes, I use that same formula as well. The 1/2 part in the formula is just used to account for the bonds. Your formula works just the same.

Anand Narayan 1G
Posts: 61
Joined: Fri Sep 28, 2018 12:15 am

### Re: Alternative version of formula

Yes, your formula work, but I prefer to use FC = Valence Electrons - (Lone Electrons + Shared Electrons/2)

Laura Gong 3H
Posts: 89
Joined: Fri Sep 28, 2018 12:26 am
Been upvoted: 1 time

### Re: Alternative version of formula

What works for me is: Formal Charge = Valence Electrons - (Dots + Dashes). Dots representing number of electrons that are unbounded and dashes representing the number of bonds.

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

### Re: Alternative version of formula

Yes it works, use whatever formula you're most comfortable with, but understand what the formula presented means.

Posts: 60
Joined: Fri Sep 28, 2018 12:27 am

### Re: Alternative version of formula

Dr. Lavelle uses FC=valence electrons - (free electrons + bound electrons/2) because it helps us to understand that each line, or bond, in the Lewis structure represents 2 electrons. You can also use FC=valence electrons - (dots+lines) though because counting each line is the same thing as multiplying each line by 2 to get the amount of electrons and then dividing it by two in the equation. The bottom line is that we should be memorizing concepts not equations.

ellienelson4F
Posts: 7
Joined: Fri Sep 28, 2018 12:27 am

### Re: Alternative version of formula

You can use both, but make sure you understand why they both work! The "dashes" represent bonds, which in the lecture formula is represented by the /2, so the numbers will come out the same for this reason.

Nicklas_Wright_1A
Posts: 60
Joined: Fri Sep 28, 2018 12:23 am

### Re: Alternative version of formula

Yes, they both work and I think your formula is much easier to remember and use.