The estimation of the alkali metals by Flame photometry is by far it most important application in routine chemical analysis. This technique has considerable appeal in the clinical chemistry field as it provides a rapid and reliable means of estimating Sodium, Potassium, Calcium, Barium, Magnesium, Lithium, and etc., in body fluids. Compounds of alkali and lakaline earth metals are thermally dissociated into atoms at the temperature of a Bunsen burner flame and that some these atoms produced are further excited to a higher level.