Absorbence spectroscopy

Reflectance spectroscopy

Fluorescence spectroscopy

Flourescence occurs when photons are absorbed by atoms, and electrons are bumped up to higher orbit -- as they release energy when they drop down to their original energy state, they release a photon. Because the electrons fall specific distances, you always get the exact same color. The color of the photon indicates how far it fell, which relates to the size of the atom. Can use any high energy light, including sunlight (although it is hard to see flourescence in presence of so much reflectance) *seems to be best for hydrocarbons, chlorophyll, and ravers

Flame emission spectroscopy

*Only for identifying pure elements.