1. A device that converts information contained in chemical or physical domain into an electrical signal or the reverse is called the

A. monochromatorB. amplifierC. transducerD. digitizerE. chart recorder

2. Which of the following is a source of excitation energy for atomic emission spectrometer?

A. laserB. tungsten lampC. globarD. nichrome wireE. flame

3. Which of the following analytical methods is not an instrumental method?

A. mass spectrometryB. gravimetryC. Raman spectrometryD. X-ray diffractionE. Coulometry

4. In which of the following regions of the electromagnetic spectrum has the argon ion laser become important radiation source in spectrometry?

A. visibleB. near-infraredC. vacuum ultravioletD. microwave

5. From the following factors, what are the two factors that limit the sensitivity of an instrument: (a) the slope of the calibration curve, (b) skills of an operator, (c) detection limit of the measuring device, (d) precision of the measuring device, (e) dynamic range of the calibration curve

A. a & bB. d & eC. a & eD. a & dE. c & e

6. A plot of the analytical signal versus analyte concentration, with all other variables held constant, is called the ____________.

A. calibration functionB. calibration curveC. analytical functionD. spectrumE. figure of merit

7. Which of the following processes is the basis of laser action?

A. stimulated emissionB. spontaneous emission

C. absorptionD. pumping

Questions 8-11 concern the following: A least-squares analysis of calibration data obtained by an instrumental method for the determination of the species X in aqueous solution yielded the equation S = 0.0670Cx + 0.031, where Cx is the X-species concentration in ppm and S is the analytical signal. The following data were obtained:

Cx (ppm) No. Repetitions N Mean Value of S Standard Deviation (ppm)0.00 25 0.031 0.00796.00 5 0.422 0.0084

18.00 5 1.248 0.0110

8. Calculate the calibration sensitivity.

A. 0.0079B. 0.0125C. 0.0084D. 0.0670

9. Calculate the analytical sensitivity at 6.00 ppm concentration of X.

A. 7.1B. 8.0C. 9.2D. 7.9E. 6.1

10. Calculate the minimum distinguishable analytical signal.

A. 0.0547B. 0.0468C. 0.0310D. 0.0675E. 0.0084

11. Calculate the detection limit.

A. 0.23 ppmB. 0.84 ppmC. 0.64 ppmD. 0.35 ppmE. 0.11 ppm

12. Which of the following types of noise is frequency independent?

A. environmental noiseB. 1/f noiseC. white noiseD. interference noiseE. flicker noise

13. Name the type of noise that can be reduced by decreasing the frequency bandwidth of the instrument.

A. thermal noise

B. chemical noiseC. flicker noiseD. slow driftsE. interference noise

14. The maximum and the minimum in the chart recorded electrical signal of 0.9 x 10-15 A were estimated to be 1.5 x 10-15 A and 0.4 x 10-15 A, respectively. Make a rough estimate of the signal-to-noise ratio for the 0.9 x 10-15 A singal.

A. 1B. 2C. 3D. 4E. 5

Questions 15-17 concern the following data obtained for repetitive weightings of a 1.004-g standard weight on a top-loaded balance:

1.003 1.000 1.0011.004 1.005 1.0061.001 0.999 1.007

15. Calculate the root-mean-square (rms) noise for the measurements.

A. 2.8 x 10-3

B. 3.2 x 10-3

C. 2.0 x 10-4

D. 1.8 x 10-5

E. 1.6 x 10-3

16. Assuming that the noise is random, calculate the signal-to-noise ratio for the balance.

A. 568B. 438C. 358D. 225E. 670

17. How many measurements would have to be averaged to measure S/N of 1000?

A. 18B. 36C. 50D. 70E. 100

18. The ground state of a molecule is its ____________ state.

A. energy at 77 KB. lowest energyC. electronic energyD. ionization energyE. vibrational energy

19. The wavenumer of radiation is

A. the reciprocal of frequency in hertzB. a discrete packet of energyC. the reciprocal of wavelength in centimetersD. the reciprocal of wavelength in nanometersE. the wavelength in centimetes

20. The bond energy of a diatomic molecule is approximately 240 kJ/mol. What is the longest wavelength of light that is capable of breaking the bond in the molecule?

A. 267 nmB. 498 nmC. 369 nmD. 620 nmE. 754 nm

21. Which of the following occurs when a monochromatic light passes from one medium to another of different refractive index.

A. its frequency changesB. its wavelength remains unchangedC. its velocity remains unchangedD. its frequency remains unchangedE. its polarization changes

Questions 22-24 concern the visible light of 650 nm that passes through a medium whose refractive index is 1.53.

22. Calculate the velocity of the passing light.

A. 3.00 x 108 m s-1

B. 1.96 x 108 m s-1

C. 2.10 x 108 m s-1

D. 3.46 x 108 m s-1

E. 2.60 x 108 m s-1

23. Calculate the frequency of the passing light.

A. 4.61 x 1014 HzB. 5.09 x 1014 HzC. 3.01 x 1014 HzD. 5.32 x 1014 HzE. 2.15 x 1014 Hz

24. Calculate the wavelength of the passing light.

A. 650 nmB. 335 nmC. 413 nmD. 425 nmE. 725 nm

25. Calculate the energy of an X-ray photon with a wavelength of 2.4 Å.

A. 8.28 x 10-16 JB. 7.36 x 10-16 JC. 6.56 x 10-17 J

D. 8.28 x 10-18 JE. 7.36 x 10-18 J

26. What type of transitions (or energy involved) can be probed with microwave photons?

A. molecular vibrationsB. valence electronsC. molecular rotationsD. nuclear transitionsE. spin orientations of electrons

27. Emission and luminescence techniques both involve the measurement of the emission of photons from excited species. What makes these techniques different?

A. excitation source of energyB. energy of the emitted photonsC. direction of the emitted photonsD. wavelength selectorE. tranducer

28. Calculate the percent transmittance of a solution with the absorbace of 0.775.

A. 26.5%B. 32.8%C. 77.5%D. 16.8%E. 50.6%

29. The molecular absorptivity of aminoacid histidine at 211-nm is 6.3 x 103 M-1 cm-1. What is the concentration of histidine in the analytical sample which shows 20% transmittance at 211 nm in a 2.0-mm cuvette?

A. 6.3 x 10-3 MB. 7.6 x 10-4 MC. 5.5 x 10-4 MD. 3.2 x 10-3 M

30. A grating has a groove density of 1800 grooves per mm. The incident beam strikes the grating at an angle of 10.0 degree. What wavelength will appear in the first order at the diffraction angle of 30.0 degree?

A. 374 nmB. 748 nmC. 215 nmD. 1213 nmE. 3740 nm

31. Using the grating and incident angle in Question 30, find the diffraction angle for a second order of 250 nm.

A. 10.0 degreeB. 20.0 degreeC. 17.0 degreeD. 37.0 degreeE. 47.0 degree

32. A linear reciprocal dispersion of the grating monochromators is 2.5 nm/mm. Find the slit width needed to obtain a 0.5-nm geometric spectral bandpass.

A. 0.5 nmB. 200.0 μmC. 400.0 μmD. 2.5 mmE. 125.0 μm

33. For the monochromator in Question 32, what is the slit-width-limited resolution?

A. 1.0 nmB. 1.5 nmC. 2.5 nmD. 5.0 nmE. 2.0 nm

34. Calculate the size of a grating with 1200 grooves/mm that is required to resolve two lithium emission lines at 4601.0 and 4603.0 Å in the first order.

A. 0.50 cmB. 0.25 cmC. 0.38 cmD. 0.47 cmE. 0.10 cm

35. Suggest a source of excitation for constructing a portable device that would be well suited for determining the iron content of natural water based upon the absorption of radiation by the red Fe(SCN)2+ complex.

A. nitrogen laserB. globarC. tungsten lampD. gas/oxygen flameE. nichrome wire