What principle does flame photometry operate on?

Flame photometry operates on the principle of the emission of light by atoms or ions in a flame. When a sample is introduced into a flame, it is vaporized and subjected to high temperatures, which provides enough energy to excite certain metal ions prevalent in the sample. As these ions return to their ground state, they emit light at characteristic wavelengths. The intensity of this emitted light is directly proportional to the concentration of the metal ions present in the sample. This allows for the quantification of specific elements based on their unique emission spectra.

Understanding this principle is crucial in analytical chemistry because it highlights the importance of thermal energy in generating measurable signals that can be interpreted for quantitative analysis. The other choices describe different analytical techniques but do not pertain to flame photometry.