flame emission spectroscopy (FES)

Principle

• when a metallic salt is heated in a flame, the energy absorbed as heat excites one or more electrons into an excited state
• when the excited electrons return to the ground state, electromagnetic radiation is emitted. The wavelength of the radiation emitted are characteristic of the atom/ion under consideration
• each metal has its own characteristic emission spectra showing emission of radiation at characteristic wavelenths

More general terms

• spectrophotometry