## Polyatomic Lewis Structures

Yolandia Winn 1A
Posts: 22
Joined: Fri Jun 23, 2017 11:39 am

### Polyatomic Lewis Structures

Why is it that we add/subtract electrons when creating lewis structures? (ex if it is molecule3+, we'd subtract 3 electrons from the entire model)

604807557
Posts: 51
Joined: Wed Nov 16, 2016 3:02 am

### Re: Polyatomic Lewis Structures

Anions gain electrons, cations lose electrons

Wu Yuchen A1
Posts: 24
Joined: Thu Jun 29, 2017 3:00 am

### Re: Polyatomic Lewis Structures

ions form when losing/ gaining several electrons, thus when drawing Lewis structure we should add/subtract electrons.

Paul Wong1B
Posts: 25
Joined: Fri Jun 23, 2017 11:39 am

### Re: Polyatomic Lewis Structures

If a molecule has a charge of 3+, it means that the molecule has 3 less electrons than it normally does. This would mean that you use 3 electrons less on the diagram than you would if you were drawing the ground state diagram. On the other hand, if a molecule were to have a 3- charge, then it would prompt an addition of 3 electrons into the lewis dot structure of the molecule.

Posts: 24
Joined: Wed Nov 16, 2016 3:03 am

### Re: Polyatomic Lewis Structures

I agree with Paul. It gets a little confusing when we are shown 2+ or 2- for example because you are technically doing the opposite.
If it shows 2+, then you are removing. If it shows 2-, then you are adding.

Manasvi Paudel 1A
Posts: 50
Joined: Sat Jul 22, 2017 3:00 am

### Re: Polyatomic Lewis Structures

The polyatomic ions aren't their usual, balanced charge so when something is 3+, it means that it has three less electrons that it would normally. Anions gain electrons and Cations lose them. When you draw lewis structures, people usually write the charge in the upper right to differentiate !