For the flame shown in Figure 9-3, calculate the relative intensity of the 766.5-nm emission line for potassium in theflame center and at the following heights above the orifice (assume no ionization and use the 2.0 cm for comparison).(a) 2.0 cm (b) 3.0 cm (c) 4.0 cm (d) 5.0 cm

For the flame shown in Figure 9-3, calculate the relative intensity of the 766.5-nm emission line for potassium in theflame center and at the following heights above the orifice (assume no ionization and use the 2.0 cm for comparison).(a) 2.0 cm (b) 3.0 cm (c) 4.0 cm (d) 5.0 cm

Principles of Instrumental Analysis

7th Edition

ISBN:9781305577213

Author:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Publisher:Douglas A. Skoog, F. James Holler, Stanley R. Crouch

Chapter7: Components Of Optical Instruments

Section: Chapter Questions

Problem 7.17QAP

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10. For the flame shown in Figure 9-3, calculate the relative intensity of the 766.5-nm emission line for potassium in the flame center and at the following heights above the orifice (assume no ionization and use the 2.0 cm for comparison). (a) 3.0 cm (b) 5.0 cm 1700 1750 5.0 1600 1800 1400 1830 4.0 1858 1863 3.0 2.0 1830 1800 1.0 1700 1.5 1.0 0.5 0.5 1.0 1.5 cm cm Burner tip Distance above orifice, cm
Assume for the following situations that Beer’s law remains linear. For (a) and (b), indicate whether the extinction coefficient ε, path length b, or concentration C is changing, and how it will change the absorbance of the solution. (a) A sample is moved from a test tube that is 1.0 cm wide to a test tube that is 1.5 cm wide. 4 (b) A sample is diluted by adding enough solvent to double its volume. (c) A solution of iron (III) chloride appears brown when in high enough concentrations. In a 1.0 cm cuvet, the absorbance of 334 nm light by a 5.4 × 10−4 M solution of FeCl3 is measured to be 1.05. What is the extinction coefficient of the FeCl3 complex at this wavelength?
Assume for the following situations that Beer’s law remains linear. For (a) and (b), indicate whether the extinction coefficient ε, path length b, or concentration C is changing, and how it will change the absorbance of the solution. (a) A sample is moved from a test tube that is 1.0cm wide to a test tube that is 1.5cm wide. (b) A sample is diluted by adding enough solvent to double its volume. (c) A solution of iron (III) chloride appears brown when in high enough concentrations. In a 1.0 cm cuvet, the absorbance of 334 nm light by a 5.4 × 10−4 M solution of FeCl3 is measured to be 1.05. What is the extinction coefficient of the FeCl3 complex at this wavelength? (d) A sample containing an unknown concentration of FeCl3 is measured to have an ab- sorbance of 0.43 at 334 nm in a 1.0 cm cuvet. What is the molar concentration of the solution?
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