3. • Used as standard method for the metal
analysis
• In atomic emission small part of sample
is vaporized forms free atom that attain
energy form excitation source results in
transition from lower to higher energy
state on returning back emit a photon of
radiation
5. Principle
• The electrons of an atom moves from
higher energy level to lower energy level,
they emit extra amount of energy in the
form of light which is consist of photons.
18. Atomizer
• Elements to be analyzed needs to be in
atomic state.
• Atomization; Conversion of sample (maybe;
solid or liquid) into free gaseous atom.
• Atomizer; Device used for atomization
20. 1. Flame Atomizer
• To produce flame, required oxidant gas
and flame gas.
• Mostly the air-acetylene flame or nitrous
oxide- acetylene flame is used.
• Liquid or dissolved samples are typically
used with flame atomizer.
22. Sub-types Of Flame Atomization
a. Continuous Atomization; samplepenetrate
the atomizer at constant speed.
a. not used for dissolved solid.*
b. Discrete Atomization; measured amount of
sample enters atomizer.
– effective when sample volume islimited.
23. 2. Electro-thermal Atomizer
• Also known as “Graphite Furnace
Atomizer”
• More convenient to uses a non-flame
method i.e. electrically heated graphite
tube.
24. Atomization Of Sample
• drying of sample
into solid
deposit.
• by heating
graphite tube at
110 ºC.
DRYING ASHING
• conversion of
organic matter in
CO2 and H2O
&volatilization
of inorganic
matter.
• by heating
graphite tube at
350-1200 ºC.
ATOMIZATION
• leads to gaseous
atom
• by raising the
temperature up to
2000-3000 ºC.
25. Advantages;
• Small sample size
• Little or no sample preparation required
• Enhanced sensitivity
• Direct analysis of solid samples
Disadvantages;
• Loss of analyte during ashing stage
• Incomplete atomization
26. Sample Handling
• The droplets of sample introduced in
atomizer should be of constant size.
• The temperature should be maintained to
obtain good reproducibility.
• The speed of introducing sample must be
equal to certain permissible band values.
• Sufficient sample volume should be
available for maximum efficiency
28. Monochromator
• It is a device use to transmit narrow band
of wavelength which is chosen from
wavelength of wider range available.
• Types of monochromator:
• Prism Monochromator
• Grating Monochromator
29. a. Prism
• When the light pass through prism it
emerges out in form of two lines or beam.
• To overcome this drawback two half
prism are placed.
• When light pass through first prism it
splits into two beams, when it reaches
second half prism recombines two beam
into single beam
30. b. Diffraction grating
• It gives better result and resolution.
• It replaced prism give linear dispersion.
• Problem occurred during the
identification of wavelength of emission
lines on photographic plate solved
through grating monochromator.
• Once we identify known reference line
and other lines identified automatically.
32. Phototube (Photo Electric Cell)
• Glass filled or vacuum tube
• Sensitive to light
• Depend on frequency and intensity of incoming
photon
• Need amplifier. But are replaced by
photomultiplier detectors.
33. Photo Multiplier Detector
• Vacuum phototubes, are extremely
sensitive detectors of light in the ultra
violet, visible, and near-infrared
region ranges of the electromagnetic
spectrum.
36. Applications
• It is used for rapid analysis of
multi-component pharmaceutical tablet.
• It is used for elemental analysis.
• It is used primarily for the identification
and determination of metals in traces
amount.
37. • It is used for determination of mineral
composition of igeous and metamorphic
rock.
• It is used for routine analysis of wear
metals in lubricating oils.
• It is used for the analysis of sodium,
potassium and lithium.