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Gernald
May 24, 2010, 08:37 AM
I've recently entered the wonderful world of O-Chem and seem to have some issues with resonance. I understand that it's just another way of looking at where electrons are, but I have some issues moving them around properly.
For example: N3CH3

CH3-N=N=N
+ -
I look at something like this and am so confused. Where do I move the electrons? Do I take from the nitrogen on the end and move it to the one in the middle to result in no weird charges, or do I do something else?

Any help would be AMAZING!!

Unknown008
May 24, 2010, 09:21 AM
Uh, what do you mean by move the electrons? :confused:

Gernald
May 24, 2010, 09:23 AM
I mean the charges, or something... I have no idea. At this point I'm kind of just going with it. Lol

Oh and I just noticed that the positive charge is supposed to be on the middle nitrogen, and the negative on the end one.

Unknown008
May 24, 2010, 09:40 AM
(I have never seen that compound, but I'll try)

If I understand your question well...

You will notice that the middle N atom has four bonds, hence it is very unstable.

(I'll talk about outermost electrons only to simplify things)
This nitrogen has initially 5 electrons, then bonding doubly with the adjacent N atoms, it now has got 9 electrons, too much for it to hold and the right N atom has 7 electrons total. The molecule therefore donates that extra electron from the middle N atom to the right N atom, so that both have an octet of electrons (stability). It's some sort of de-localisation I guess. Since the middle N lost an electron, it becomes +ve and the riht electron becomes -ve as it has received an electron.