LOYOLA COLLEGE (AUTONOMOUS), CHENNAI – 600 034
M.Sc. DEGREE EXAMINATION – BIO MEDICAL INSTRU. SCIENCE
SUPPLEMENTARY EXAMINATION – JUNE 2009
CH 2901 - INSTRUMENTAL METHODS OF CHEMICAL ANALYSIS
Date & Time: 26/06/2009 / 10:00 - 1:00 Dept. No.
Max. : 100 Marks
PART- A
Answer ALL the questions :
(10×2 = 20)
1. What weight of HCl is present in 155 mL of a 0.540 M solution?
2. The absorption of acetone shifts to 279 nm in hexane, 272 nm in ethanol and 264.5 nm in
water. Why?
3. What is the relation between fluorescence intensity and concentration?
4. Why a separate lamp is required to determine each element in AAS?
5. What is a buffer solution? How will you prepare phosphate buffer?
6. Define residence time.
7. In I.R spectroscopy the carbonyl stretching frequency for formaldehyde and acetaldehyde
occurs at 1750 cm-1and 1745 cm-1 respectively. Give reason.
8. What is meant by base peak?
9. Which type of nuclei show NMR spectra?
10. Define unit cell.
PART- B
Answer any EIGHT questions:
(8×5= 40)
11. 5 g of NaCl is dissolved in 1000g of water. If the density of the resulting solution is 0.997 g
per mL, calculate the molality, molarity, normality, assuming volume of solution is equal to
that of solvent.
12. Explain bathochromic and hypsochromic shift with examples.
13. Compare the principle of turbidimetry with colorimetry.
14. How will you determine thiamine by fluorimetry?
15. Explain with diagram the working of inductively coupled plasma atomiser in AAS.
16. For the cell Hg,Hg2Cl2(s);KCl(sat)//H+(unknown);Q,QH2,Pt the E.M.F
at 25°C is 0.2640 V.Calculate the pH of the solution at this temperature.
Ecalomel= +0.2422 V at 25°C and E° (H+,Q,QH2) =+0.6996 V.
16. Write briefly about the different methods of sample injection involved in HPLC.
17. On the basis of I.R spectra distinguish the following compounds i)n- Hexane and ii) 1-Hexyne.
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18. Explain the chemical shift values for the following molecules.
CH3-CH3 δ 1.1 ppm
,
CH2=CH2 δ 4.6-5.9 ppm , CH≡CH δ 2-3 ppm
20. Define chemical shift and spin-spin splitting.
21. The diffraction angle in the first order diffraction of a crystal is 14.5°, when
X-rays of wave length 0.61Å is used. Calculate the inter planar distance in
the crystal.
22. Mention the applications of neutron diffraction.
PART-C
Answer any FOUR question: (Q.No. 28 is compulsory)
(4×10=40)
23. Describe the instrumentation of single beam spectrophotometer with a
block diagram.
24. a) Give an account of Hollow cathode lamp.
(5)
b) How are spectral and chemical interferences prevented or corrected in
atomic absorption determination?
(5)
25. a) Find the pH of a solution in which [H+]= 4.0×10-5 mol L-1.
(3)
b) How will you determine the pH of a solution using hydrogen electrode? (7)
26. a) Write briefly about the structure of NaCl.
b) Mention the principles involved in electron diffraction.
(5)
(5)
27. a) Hydrogen bonding shifts the position of absorption in I.R spectroscopy.
Give reason.
(5)
b) Give the fragmentation pattern of 1-butanol.
(5)
28. A compound has the molecular formula C3H8O exhibit the following spectral data.
I.R ν in cm-1
1
3400 (s)
HNMR δin ppm : 0.9[3H,t] , 1.6 [2H,m], 3.6 [2H,t], 4.9 [1H,s]
Mass m/z
60,31(100%),29,15.
Deduce the structure of the compound.
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