Atomic Absorption Spectroscopy - Principles

Principles

The technique makes use of absorption spectrometry to assess the concentration of an analyte in a sample. It requires standards with known analyte content to establish the relation between the measured absorbance and the analyte concentration and relies therefore on the Beer-Lambert Law. In short, the electrons of the atoms in the atomizer can be promoted to higher orbitals (excited state) for a short period of time (nanoseconds) by absorbing a defined quantity of energy (radiation of a given wavelength). This amount of energy, i.e., wavelength, is specific to a particular electron transition in a particular element. In general, each wavelength corresponds to only one element, and the width of an absorption line is only of the order of a few picometers (pm), which gives the technique its elemental selectivity. The radiation flux without a sample and with a sample in the atomizer is measured using a detector, and the ratio between the two values (the absorbance) is converted to analyte concentration or mass using the Beer-Lambert Law.

Read more about this topic:  Atomic Absorption Spectroscopy

Famous quotes containing the word principles:

    Syntax is the study of the principles and processes by which sentences are constructed in particular languages. Syntactic investigation of a given language has as its goal the construction of a grammar that can be viewed as a device of some sort for producing the sentences of the language under analysis.
    Noam Chomsky (b. 1928)

    Our national determination to keep free of foreign wars and foreign entanglements cannot prevent us from feeling deep concern when ideals and principles that we have cherished are challenged.
    Franklin D. Roosevelt (1882–1945)

    ...at this stage in the advancement of women the best policy for them is not to talk much about the abstract principles of women’s rights but to do good work in any job they get, better work if possible than their male colleagues.
    Virginia Crocheron Gildersleeve (1877–1965)