EDIT: This may be better in the Chemistry forum, I'm really not sure. I'm just doing some basic qualitative MO theory for my first year chemistry class, and i am becoming quite confused. My text says shows your typical 'dumbbell' model of a p orbital, each a different colour, and states "The two lobes of the p orbitals are of opposite phase."...without actually explaining what phase is. Is phase just another name for it's orientation along an x y z axis, or does it have to do with the magnetic moment?