NATIONAL OPEN UNIVERSITY OF NIGERIA
UNIVERSITY VILLAGE, PLOT 91 CADASTRAL ZONE, NNAMDI AZIKIWE EXPRESS WAY, JABI – ABUJA.
FACULTY OF SCIENCES
DEPARTMENT OF PURE AND APPLIED SCIENCES
FEBRUARY/MARCH 2018 EXAMINATION
COURSE CODE: CHM 306
COURSE TITLE: INSTRUMENTAL METHODS OF ANALYSIS
TIME: 2 HOURS
INSTRUCTION: Question one is compulsory. Answer question one and
any other three questions.
QUESTIONONE
1a) Calculate the concentration of a sample solution whose absorbance and
molar absorptivity at 270nm is 1.92 and 19400 respectively. 4 marks
1b) What happens when radiation and matter interact?6 marks
1ci) Discuss the basic concept of X-ray diffraction method.7 marks
1cii)Explain briefly Polarography.4 marks
1dii) State one use of each of the following
I. Infrared spectroscopy
II. X- ray diffraction method
III. Flame Emission and Flame Atomic Absorption Spectroscopy
IV. Nuclear Magnetic Resonance Spectroscopy 4 marks
QUESTION TWO
2ai Describe briefly the basic principle of Nuclear Magnetic Resonance (NMR) spectroscopy. 7marks.
2aii) What factor accounts for the difference, in the pattern of NMR spectrum of
hydrogens in different organic molecules.4 marks
2b) Enumerate on the function of the parts of a spectrophotometer.4 marks
QUESTION THREE
Explain how the concentration of a coloured sample can be estimated by colorimetry.
15 marks
QUESTION FOUR
4ai) What is infrared spectroscopy? 11/2 marks
4aii) How would you determine the functional groups present in an organic molecule using infrared spectroscopy? 8 marks
4b) Distinguish between Infrared spectrometer and Fourier Transformer Infrared spectrometer. (41/2 marks)
QUESTION FIVE
5a) With the aid of a well labelled schematic diagram, expatiate on the working principle of Flame Atomic Absorption Spetroscopy. 101/2 marks.
5b Distinguish between the following terms used in Flame Atomic Absorption Spectroscopy
i. Interference
ii. Sensitivity
iii. Detection Limit (41/2 marks)
You can get the soft copy for this course or the exam summary answers for this course from 08039407882
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