## Central atom

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

Sofia Q
Posts: 49
Joined: Sat Aug 17, 2019 12:15 am

### Central atom

When setting up Lewis structures, should we always ensure that the formal charge of our central atom is 0? Are there any exceptions?

John Arambulo 1I
Posts: 58
Joined: Sat Jul 20, 2019 12:15 am

### Re: Central atom

You have to take into account all of the atoms in the Lewis structure and the overall charge of the molecule because it is more stable when the negative formal charge is on the more electronegative atom and the positive formal charge is on the less electronegative atom.

Amy Kumar 1I
Posts: 114
Joined: Thu Jul 11, 2019 12:15 am

### Re: Central atom

The formal charge of the central atom might not always be 0, but as long as the the sum of all the formal charges add up to the charge of the overall molecule, it's fine.

cassidysong 1K
Posts: 100
Joined: Fri Aug 30, 2019 12:15 am

### Re: Central atom

What the people of above me said :). The center atom's formal charge may not always be zero, if there is a choice between an outer atom with a formal charge of zero and the center atom with zero than it is best to have the center atom with zero.

Maeve Miller 1A
Posts: 51
Joined: Fri Aug 09, 2019 12:16 am

### Re: Central atom

Ideally, you'd want all the elements within the atom to have a formal charge of zero because it would make it extremely stable. However, this is not always the case, and it is best to make the overall charge neutral.

Kassidy Ford 1I
Posts: 103
Joined: Sat Aug 17, 2019 12:16 am
Been upvoted: 1 time

### Re: Central atom

do resonance structures depend only on the FC of central atom or on all of the atoms

Junwei Sun 4I
Posts: 125
Joined: Wed Oct 02, 2019 12:16 am

### Re: Central atom

Formal charge of the central atom is not always zero. It is better to look at formal charges of all atoms inside a structure. With more atoms having a formal charge of zero the structure is the most stable. And in the case when the formal charges are not zero, the more electronegative atom should have a more negative formal charge.

Kate Osborne 1H
Posts: 102
Joined: Fri Aug 30, 2019 12:16 am

### Re: Central atom

When drawing lewis structures your goal should not be to have the central element have a formal charge of zero but rather have the most elements have a formal charge of zero and the most electronegative elements carry the negative formal charges.