As AAS is much more sensitive than FES , AAS is used as a reference method for many analytical procedures. ... In AAS, however, the flame serves to dissociate the element from its chemical bonds and place it in a ground state at which it is capable of absorbing light of a wavelength specific for the element.
What is the difference between atomic absorption and atomic emission spectroscopy?
Atomic absorption spectra are produced when ground-state atoms absorb energy from a radiation source . Atomic emission spectra are produced when neutral atoms in an excited state emit energy on returning to the ground state or a lower-energy state.
What is the difference between flame emission photometry and atomic absorption spectrophotometry?
The key difference between flame emission spectroscopy and atomic absorption spectroscopy is that during flame emission spectroscopy, certain wavelengths are emitted from atoms, whereas during atomic absorption spectroscopy, certain wavelengths are absorbed by atoms.
What are the advantages of AAS over Fes?
Advantages of Atomic Absorption over Flame Photometry:
(1) It does not suffer from spectral interference, which occurs in flame emission spectroscopy. (2) By atomic absorption technique, traces of one element can easily be determined in presence of high concentration of other elements .
What is the difference between AAS and AES?
While AAS quantifies the absorption of electromagnetic radiation by well-separated neutral atoms, AES measures emission of radiation from atoms in excited states .
Which detector is used in flame photometer?
The flame photometric detector (FPD) allows sensitive and selective measurements of volatile sulphur and phosphorus compounds. The detection principle is the formation of excited sulphur (S 2 *) and excited hydrogen phosphorous oxide species (HPO*) in a reducing flame.
What is atomization in AAS?
In AAS the sample is most commonly introduced as a solution. ... When the mist reaches the flame, the intense heat breaks up the sample into its individual atoms . This final process is called atomization.
What are the applications of atomic absorption spectroscopy?
- Agriculture – analyzing soil and plants for minerals necessary for growth.
- Chemical – analyzing raw chemicals as well as fine chemicals.
- Food Industry – quality assurance and testing for contamination.
- Forensic’s – substance identification.
What is atomic absorption used for?
Atomic absorption spectrometry (AAS) is an easy, high-throughput, and inexpensive technology used primarily to analyze elements in solution . As such, AAS is used in food and beverage, water, clinical research, and pharmaceutical analysis.
What are the advantages of atomic absorption spectroscopy?
The main advantages of AAS are that it is relatively inexpensive and easy to use , while still offering high throughput, quantitative analysis of the metal content of solids or liquids. This makes it suitable for use in a wide range of applications.
What is the principle of AAS?
AAS is an analytical technique used to determine how much of certain elements are in a sample. It uses the principle that atoms (and ions) can absorb light at a specific, unique wavelength . When this specific wavelength of light is provided, the energy (light) is absorbed by the atom.
Which radiation source is used in AAS?
Radiation sources used in AAS are hollow cathode lamps, electrodeless discharge lamps, continuous light sources, and vapor discharge lamps , which are efficiently used in AAS systems. Among these radiation sources, hollow cathode lamps are more commonly used in AAS systems.
Why is it difficult to use atomic absorption for qualitative analysis?
AAS is not suitable for (i) analysis of ametals because of their resonance absorbance in vacuum UV (< 200 nm) where the components of air (N 2 , O 2 ) absorbs the radiation, and (ii) qualitative analysis because the method requires the change of radiation source for each analyte element and adjustment of instrumental ...
Is AAS qualitative or quantitative?
Atomic absorption spectroscopy (AAS) and atomic emission spectroscopy (AES) is a spectroanalytical procedure for the quantitative determination of chemical elements using the absorption of optical radiation (light) by free atoms in the gaseous state.
What type of result can AAS produce?
AAS provides a high degree of accuracy . Normally results fall within a range of 0.5 per cent to 5 per cent accuracy, but this may improve further depending on the standards set for testing and analysis. It is a highly sensitive method of analysis. In a given material, it can measure parts per billion of a gram.
What is the correct order of AAS?
The standard AAS instrument consists of four components: the sample introduction area, the light (radiation) source, the monochromator or polychromator, and the detector (figure 1). Figure 1. The basic components of an AAS system.
