Classic flame photometric experiment:

In a classic flame photometric experiment, a solution of the analyte is aspirated within the burner and dispersed into the flame as a fine spray in a process known as nebulisation. A number of procedures occur in the flame to produce the gaseous atoms and ions in the excited state. An intensity of the emitted radiation is then measured for the qualitative and quantitative determination of the analyte.

A flame could be described as a steady state gas phase reaction that takes place along with emission of light. These are produced through burning a mixture of fuel and air or oxidant within a burner. The maximum operating temperature of the flame is determined through the identity of fuel and oxidant while the exact temperature is fixed through the ratio of fuel and oxidant. Either pre-mix (or laminar) or unpremix (or turbulent) flames are used within flame photometry. Inside the former, a fuel and oxidant are well mixed before combustion, while in later these are mixed in the flame itself.

The instrument used in flame photometry is known as flame photometer; it consists of a flame atomiser, monochromator, flame burner, detector, amplifier and readout device. The simple inexpensive flame photometer employing glass filters is enough for routine analysis of alkali and alkaline earth metals by more expensive sophisticated instrument using monochromator might be needed for analysis of other elements.