LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034
M.Sc. DEGREE EXAMINATION - FOOD CHEMISTRY & FOOD PROCESSING
FIRST SEMESTER – APRIL 2011
FP 1802 - APPLICATIONS OF SPECTROSCOPY
Date : 19-04-2011
Time : 1:00 - 4:00
Dept. No.
Max. : 100 Marks
Part- A
(10  2 = 20 marks)
Answer ALL questions.
1. Calculate the UV absorption of maximum of
2. Define Zero Point energy.
3. Calculate the number of normal modes of vibration for the following molecules
(i) H2O
4.
(ii)
NH3
What is nebulizar?
5. State Lambert-Beers’s Law.
6. What do you know about M+ and M+. ion?
7. What is typical in the Mass spectrum of a compound containing (i) one Bromine atom (ii) one
Chlorine atom?
8. What is meant by (n + 1) rule in spin- spin coupling?
9. Why TMS is used as a reference in NMR spectroscopy?
10. How many spin states are possible for 1H nucleus?
Part – B
Answer any EIGHT questions.
(8  5 = 40 marks)
11. How will you distinguish between cis- and trans- isomers of stilbene using UV-Visible
Spectroscopy?
12. The frequency of C=C absorption in the IR spectrum of maleic acid is much greater than
that in Fumaric acid. Explain
13. Discuss the different types of interfaces encountered in Atomic Absorption Spectroscopy.
14. Using Woodward Fiesher rules calculate λmax of the following molecules.
(i)
(ii) (CH3)2C=CH-CO-CH3
15. Sketch the block diagram of the instrument used in UV-Visible spectroscopy and explain the
functions of various parts.
16. Explain the effect of Polarity of the Solvent on UV- visible spectroscopy.
17. Sketch the expected PMR spectra of the following compounds taking TMS as the
Standard reference.
i)
CH3-CH2-Cl
ii) CH2Br-CH2Br
18. Acetylene protons are more shielded than ethylenic protons. Explain
19. What is Nitrogen rule? Explain with examples.
20. Give five important features of parent ion peak.
21. Discuss the general fragmentation modes in Mass spectroscopy choosing any one
Example.
22. Write a short note on chemical exchange as observed in NMR spectroscopy.
Part-C
Answer any FOUR questions.
23. a) What is the principle involved in AAS ?
(4  10 = 40 marks)
(2)
b) What are the advantages of AAS over Flame emission spectroscopy?
(3)
c) Discuss the analysis of Lead by Atomic Absorption Spectroscopy
(5)
24. a) The carbonyl stretching frequency of methyl-vinyl ketone is 1640 cm-1 where as for acetophenone
it is 1693 cm-1. Explain (5)
b) Write a note on Fermi resonance (5)
25. a) How is quinine estimated fluorimetrically?
b) Discuss any three applications of IR Spectroscopy.
26. Write brief notes on the following
(i) Shielding and deshielding.
(ii) Spin-spin splitting
(iii) Spin-spin relaxation
27. Define the tern chemical shift and describe the factors which influence it.
28. What is Spin-Spin coupling? Explain it for the following compounds.
i) CH3-CHO
ii) CH3-CHBr2
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(3)