flame photometry involves the determination of concentration of alkali and alkaline earth metals present in a sample based on the radiation emitted by it when the sample is atomized to a flame
A traditional and simple method for determining sodiumand potassium in biological fluids involves the technique of emission flame photometry. This relies on the principle that an alkali metal salt drawn into a non-luminous flame will ionise, absorb energy from the flame and then emit light of a characteristic wavelength as the excited atoms decay to the unexcited ground state. The intensity of emission is proportional to the concentration of the element in the solution. You are probably familiar with the fact that if you sprinkle table salt (NaCl) into a gas flame then it glows bright orange (KCl gives a purple colour). This is the basic principle of flame photometry. A photocell detects the emitted light and converts it to a voltage, which can be recorded. Since Na+ and K+ emit light of different wavelengths (colours), by using appropriate coloured filters the emission due to Na+ and K+ (and hence their concentrations) can be specifically measured in the same sample
Principle of flame photometry
Flame photometry relies upon the fact that:
· the compounds of the alkali and alkaline earth metals can be thermally dissociated in a flame and
· that some of the atoms produced will be further excited to a higher energy level.
When these atoms return to the ground state they emit radiation which lies mainly in the visible region of the spectrum. Each element will emit radiation at a wavelength specific for that element. The measurement of the emitted radiation forms the basis of flame photometry.
The instrument of flame photometry is called the photometer or flame atomic emission spectrometer. A solution is aspirated into the flame, and studied.
It is a simple and not very expensive method to quantitatively determine traces of alkali or alkali earth metals.
what is flame photometer
Because the sodium concentration is too high, out of the determination range of the instrument.
· Analysis of industrial water, natural water for determining elements responsible for hard water (magnesium, barium, calcium etc.) is standard procedure in many laboratories. · In glass industry, flame photometry is used in determining of sodium, potassium, boron, lithium etc. · In cement industry, this method is used in estimation of sodium, potassium, calcium, magnesium, manganese, as well as lithium. · Analysis of ash by flame photometer is routinely carried out in various industries for estimating alkali and alkaline earth metals as their oxides. · Flame photometry is extensively used in estimation of alkali-alkaline earth metals as well as other metals present in metallurgical products, catalysts, alloys etc. · Flame photometry has also been used in determination of certain metals like lead, manganese, in petroleum products like gasoline, lubricating oils and organic solvents.
Since the temperature isn't high enough to excite transition metals, the method is selective toward detection of alkali and alkali earth metals.
- use a flame test to distinguish between sodium and potassium - use flame photometry to determine sodium and potassium - heat sodium carbonate and collect the gas in a beaker with water: the gas released is carbon dioxide; see the bubbles. Measure the pH; it will be more than 7.
A yellow flame is named as a safety flame as it isn't as hot as the blue flame
Flame photometry can be used for the measurement of elements which can easily be excited like Ca, K, Na, Ba, Cu etc. However due to low temperature of flame the elements like Fe can not be excited and hence not measured using Flame photometry.
Two common methods are atomic absorption spectrophotometry and flame photometry.
Roland. Herrmann has written: 'Flammenphotometrie' -- subject(s): Flame photometry
Because the sodium concentration is too high, out of the determination range of the instrument.
NOTHING 2. If the fluid contained some element, e.g. sodium or calcium, then the flame would show the colour appropriate to that element. Flame photometry relies on this principle.
Examples: emission spectrometry, flame photometry, atomic absorption, etc.
· Analysis of industrial water, natural water for determining elements responsible for hard water (magnesium, barium, calcium etc.) is standard procedure in many laboratories. · In glass industry, flame photometry is used in determining of sodium, potassium, boron, lithium etc. · In cement industry, this method is used in estimation of sodium, potassium, calcium, magnesium, manganese, as well as lithium. · Analysis of ash by flame photometer is routinely carried out in various industries for estimating alkali and alkaline earth metals as their oxides. · Flame photometry is extensively used in estimation of alkali-alkaline earth metals as well as other metals present in metallurgical products, catalysts, alloys etc. · Flame photometry has also been used in determination of certain metals like lead, manganese, in petroleum products like gasoline, lubricating oils and organic solvents.
this technique is used for the determination of sodium potassium and lithium (in case of Lithium therapy) in biological specimens received in laboratories
The sulfate ion is precipitated with barium chloride.The presence of sodium can be tested by flame photometry.
Since the temperature isn't high enough to excite transition metals, the method is selective toward detection of alkali and alkali earth metals.
Berry, Chappell & Barnes (1946) showed that, in estimating sodium and potassium by flame photometry, there were definite improvements in precision and accuracy when lithium was added to the samples as an internal standard (compare Spencer, 1950; Bernstein, 1952). The lithium internal standard signal reduces fluctuation in flame conditions, drift, and dilution errors—ensures reproducible results and precise measurements. The fully automatic ignition and flame optimization sequences reduce set up and calibration time. An automatic gas shutoff mechanism activates if the flame is accidentally extinguished. The monitoring and control software make operation simple and allow measurements only after blanking and calibration.
Bruce Steiner has written: 'The present state of radiometry and photometry' -- subject(s): Photometry, Radiation, Measurement