Polyatomic Lewis Structures

[Yolandia Winn 1A]

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]

Anions gain electrons, cations lose electrons

[Wu Yuchen A1]

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

[Paul Wong1B]

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.

[Natalie Espadas 1A]

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]

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 !