Caffeine is a polar molecule. One hint is because it dissolves in water - although that fact does not mean absolutely it is polar. The two carbonyl groups greatly add to the molecule's polarity along with the lone pair of electrons on the nitrogens.
In fact you can call caffeine both polar and nonpolar, as caffeine (or 1,3,7-trimethylxanthine) consist of both polar and nonpolar components.. On the internet I've seen a lot of people using caffeines ability to disolve in water as an argument for it to be polar.. This is not a good argument though, as caffeine in fact disolves in oils too due to the nonpolarity which I mentioned..
Nonpolar
nonpolar
It is nonpolar
nonpolar
nonpolar
nonpolar
Polar
polar
nonpolar. The fat molecules in peanut butter are nonpolar, that is why peanut butter doesn't evenly mix with water, a polar substance.
Polar substances dissolve other polar substances, and nonpolar substances dissolve other nonpolar substances. A polar substance cannot dissolve a polar substance and a nonpolar substance cannot dissolve a polar substance.
The shape is trigonal bipyramidal and all the atoms on the outside are the same so the charges cancel eachother. Nonpolar