(a)
Interpretation:
At higher temperature rate, transition of atoms of sodium occurs from 4s to 3p state and the average wavelength of sodium due to the emission is 1139 nm. Ratio of excited state 4 seconds to ground state 3seconds needs to be calculated for acetylene- oxygen flame of 3000oC.
Concept introduction:
Calculation of ratio is done by using the Boltzmann equation, given as-
Where,
Nj = no. of ions in excited state
No = no. of ions in ground state
Ej = energy difference of excited state and ground state
gj = statistical weight for excited state
go = statistical weight for ground state
k= Boltzmann constant
T = absolute temperature
Energy of atom is calculated by the following formula-
Where,
h= Planck’s constant
c = light velocity
λ= wavelength
Ej= energy difference
(b)
Interpretation:
Ratio of excited state 4s to ground state 3s needs to be calculated for an inductively coupled plasma source of 9000oC.
Concept introduction:
Calculation will be done using the following formulas-
And
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Principles of Instrumental Analysis
- In high-temperature sources, sodium atoms emit a doublet with an average wavelength of 1139 nm. The transition responsible is from the 4s to 3p state. Set up a spreadsheet to calculate the ratio of the numberof excited atoms in the 4s state to the number in the ground 3s state over the temperature range from anacetylene-oxygen flame (3000°C) to the hottest part of an inductively coupled plasma source (8750°C).arrow_forwardA 50.0 mg sample was dissolved in acid and then diluted to a total volume of 50.00 mL. If 1.000 mL ofthis solution was then diluted to 50.00 mL with water. If this diluted solution had a transmittance of 0.275 at520 nm, what is the concentration of KMnO4 in ppm in this diluted solution, assuming no interference fromother species at this wavelength?arrow_forwardThe first excited state of Ca is reached by absorption of 422.7-nm light. (a) What is the energy difference (J) between the ground and excited states? (b) The degeneracies are g*/g0 3 for Ca. Find N*/N0 at 2 500 K. (c) By what percentage will the fraction in (b) be changed by a 15-K rise in temperature? (d) Find N*/N0 at 6 000 K.arrow_forward
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- Principles of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning