CHEMISTRY COMMUNITY

I have in my notes that when calculating formal charge, the most electronegative element will be more stable with a negative charge. Why is this so/why not with 0 charge?
Thank you so much!

When you draw Lewis structures, the most stable form would have 0 formal charges. Sometimes, you might run into structures that have unavoidable formal charges. In these cases, there is a preference for the more electronegative atom to carry the negative formal charge, and it is more stable for the less electronegative atom to carry the positive formal charge.

Oooh okay! Thank you so much!

If a certain Lewis Structure has an uneven distribution of charges (uneven distribution defined as not all atoms having a formal charge of 0) then the most electronegative atom will typically have a negative formal charge. A TA explained that this would depict a more stable resonance as the more electronegative atom has the greatest pull on the electrons. This pull would most likely lead to a negative formal charge on the atom. However, this does not necessarily mean that the most electronegative atom ALWAYS needs to have a negative charge. If the Lewis Dot Structure can be constructed so each atom has a formal charge of zero, this is still said to be more favorable.