I was looking at this example :
http://ars.sciencedirect.com/content/image/1-s2.0-S1386142502001129-gr1.gif (picture also attached)
Is the Reason they show nitrogen as having a positive charge because it is sharing two of its electrons with carbon, when in covalent bonds it usually shares 1.
And is the reason why oxygen has a negative charge because it picked up its original electron it shared with carbon as well as one of carbons electron?
thank you