Flame photometry, also known as flame emission spectroscopy, is an analytical technique first introduced in the 19th century, primarily for the qualitative and quantitative analysis of alkali and alkaline earth metals like sodium and potassium. This method works by measuring the intensity of light emitted when metallic ions are introduced into a flame, with specific wavelengths corresponding to different elements. While flame photometry is a simple and cost-effective process, it has limitations in accurately measuring higher concentrations of certain metals and cannot detect non-radiating elements like carbon and hydrogen.

1. FLAME PHOTOMETRY
Flame Atomic Emission Spectroscopy
Presented by
Javed

2. Definition
Flame photometry is also called as flame emission
spectroscopy. Since neutral atoms are involved in the
emission of radiation at specific wavelength when
introduced into the flame.
Principle
The principle of flame photometer is based on the
measurement of the emitted light intensity when a
metal is introduced into the flame.

3. Introduction
 It is a qualitative and quantitative analytical technique.
 Flame photometry has been proven standard method for the analysis of
sodium and potassium for the last 70 years.
 Richardson, John Berry and Robert hood developed an instrument
and they named as Flame photometer.
 This technique is introduced by bunsen and Kirchoff in 19th century.
They showed that the radiation emitted from the flame depends on the
characteristic element present in the flame.
 The introduced elements get excited to even higher levels. But these
atoms are not stable at higher levels.

4.  Hence these atoms emit radiation when returning back to the ground
state.
 These radiations generally lie in the visible region of the spectrum.
 Each of the earth metals has a specific wavelength.
Element Emitted wavelength Flame colour
Sodium 589 nm Yellow
Potassium 766 nm Violet
Barium 554 nm Lime Green
Calcium 622 nm Orange
Lithium 670 nm Red

5. Some basic steps
 Liquid sample.(metallic salt solution )
 Formation of droplets.
 Fine residue.
 Formation of neutral atoms.
 Excitation of atoms by thermal energy.
 Emission of radiation of specific wavelength.
 Measurement of emitted radiation.

6. Instrumentation of flame photometry
Fig-Flame Photometry

7. 1. Source of flame
A Burner in the flame photometer is the
source of flame. It can be maintained in at a
constant temperature.
Fuel-Oxidant mixture Temperature (°C)
Natural gas-Air 1700
Propane-Air 1800
Hydrogen-Air 2000
Hydrogen-Oxygen 2650
Acetylene-Air 2300
Acetylene-Oxyen 3200
Acetylene-Nitrous oxide 2700
Cyanogen-Oxygen 4800

8. 2. Atomizer and mixing
Atomizer is used to send homogeneous solution
into the flame at a balanced rate.
3. Optical system
The optical system consists of convex mirror and
convex lens. The convex mirror transmits the light
emitted from the atoms. Convex mirror also helps
to focus the emissions to the lens. The lens helps
to focus the light on a point or slit.

9. 4. Simple colour filters
The reflections from the mirror pass through the
slit and reach the filters. Filters will isolate the
wavelength to be measured from that of
irrelevant emissions.
5. Photo-detector
The intensity of radiation emitted by the flame is
measured by photo detector. Here the emitted
radiation is converted to an electrical signal with the
help of photo detector. These electrical signals are
directly proportional to the intensity of light.

10. 6. Amplifier and Display
Amplifier amplify the final result and show to the
display of the computer.

11. Various process involved in the flame
photometry.
1. Desolvation
2. Vaporization
3. Atomization
4. Excitation of elements
5. Emission

12. Applications
1.Qualitative analysis
 Flame photometry is used to identify the elements present in
the sample.
1.Quantitative analysis
 Concentration of the sample can be detect by this method.
 Concentration of calcium in serum.
 Concentration of sodium, calcium and potassium present in urine.
 Assay of potassium chloride in syrup.

13. Advantages-
 Simple process.
 Inexpensive.
 Earth elements can be determined.
 Quick process.
Disadvantages-
 The concentration of the metal ion in the solution cannot be measured
accurately.
 It is difficult to obtain the accurate result of the compound ion with
higher concentration.
 The elements such as carbon, hydrogen and halides cannot be
detected due to its non radiating nature.