## Formal Charge for Lewis Structures

RRahimtoola1I
Posts: 102
Joined: Fri Aug 09, 2019 12:15 am

### Formal Charge for Lewis Structures

So I went to the UA review session on Friday and they discussed using formal charge to determine the best way to draw a Lewis Structure. I've been trying to use that but it isn't working and I keep getting the wrong answer for the homework. Is there a certain time when we should or shouldn't use the formal charge?

Matthew Chan 1B
Posts: 111
Joined: Sat Sep 07, 2019 12:16 am

### Re: Formal Charge for Lewis Structures

My TA told me whenever drawing Lewis structures, we should always try and calculate formal charges. We should do this to make sure we're drawing the most accurate structure that we can.

JChen_2I
Posts: 107
Joined: Fri Aug 09, 2019 12:17 am

### Re: Formal Charge for Lewis Structures

We should always use formal charge but remember that the sum of the formal charges of all the atoms should equal the charge of the compound. Check that the octet rule is satisfied and keep in mind that certain elements can have expanded or incomplete octets too.

Kehlin Hayes 4C
Posts: 50
Joined: Wed Sep 18, 2019 12:17 am

### Re: Formal Charge for Lewis Structures

Calculating the Formal Charge is a great way to check if the molecule has the correct structure and the correct charge its supposed to have as well as taking the average of all these different structures get us the resonance which the formal charge is calculated for all the structures.

Ashley Osorio
Posts: 54
Joined: Thu Jul 11, 2019 12:17 am

### Re: Formal Charge for Lewis Structures

Wait, when we get a bond with resonance, do we draw all the possible lewis structures AND their formal charges?? thats a lot haha