Also how long does the smell on colgone last? I know with perfume it is layered so it can last for a day or two. Also What about body sprays, they are extremely popular here in college.
Depends on the cologne. Also depends on the percentage of aromatic compounds. As the percentage of aromatic compounds increases, so does the intensity and longevity of the scent created.(thanks to wikipedia for the info below)
IMO, a good perfume should last at least a decade to be considered good. I have a couple older than that.
As blary54 says it depends on the concentration. Cologne can last 2-3 hours while perfumes can last more than 24.
As for body sprays... why buy them when you can get good EDTs that last longer, smell better and are more concentrated? There are a lot of good EDTS that smell very good for a very modest price.