Why are there no formal charges on the 1st compound? I am specifically referring to the nitrogen atom, which I would think should exhibit a +2 formal charge? However, in David Klein's organic chemistry textbook it is said that the 1st compound shows no formal charge anywhere. The second compound, of course, exhibits a +1 formal charge on the nitrogen atom and -1 formal charge on the oxygen atom. This would make more sense if I were to take into account the lone pair for Nitrogen in compound 1 (and the 2 lone pairs for oxygen), but then why would they hide the lone pairs in compound 1 and exhibit them in compound 2? Please, correct my incorrect thinking.
Drawing common electron pairs like they appear in most organic molecules is only then relevant, when
- they play a keyrole in the reaction process
- they should explain a special molecule structure
- they are of an unusual quantity and thus resulting in a (intermolecular) formal charge
Otherwise especially molecules with a lot of atoms with unpaired electrons (e. g. saccharides) can get confusing. And in addition: they take more time to draw ;) Of course when learning organic chemistry its good to think of them a lot, because of their high reaction potential.
You can be a 100 % sure that when they would not be there in compound 1 that it would be highlighted somehow, because that would result in a very unstable state.