Huckel's rule for Aromaticity--what is n? 1. The problem statement, all variables and given/known data Probably a really stupid question. When using Huckel's rule to figure out if a cyclic compound is aromatic or not, and considering that it must have 4n + 2 pi electrons, how do I figure out what n is? 2. Relevant equations 4n + 2 3. The attempt at a solution I'll just use Benzene as an example, but I have tried on many other compounds. I have tried using the number of carbons in the ring (n is one for benzene but there are six carbons, so that doesn't work), the degree of unsaturation (which is 4 for benzene, not one), the number of hetero/electronegative atoms (obviously this doesn't work), and some other less impressive ways of thinking about it. I can't find an explanation anywhere in the textbook and am a bit confused about why they changed n from signifying 'number of carbons' to something else without telling anyone. Someone told me n is the number of cyclic rings within a compound, which makes sense for benzene (1) and napthalene (2) but if that's the case then I don't know what to do with bigger aromatics such as octo/nano/decatriene--I'm not sure if those in particular are even aromatic due to my lack of understanding of this simple rule, but I did see some examples of bigger rings that had n values of two. If anyone can shed any light on this at all I would appreciate it. I really can't advance with this material unless I grasp this. Thanks.