Master of Science II (Physical Chemistry) Examination: Oct/Nov
2016 Semester IV (Old CGPA)
SLR No. Day
Date Time Subject Name Paper
No. Seat No.
SLR SD
255
Tuesday
22/11/2016
02.30 PM
To
05.00 PM
Molecular structure-II
C
XV
Instructions: Attempt in all Five questions.
Section I is compulsory.
Attempt any two questions from Section II and any two questions
from Section III
Answer to all questions (Section II and III) should be written in
the one answer book.
All questions carry equal marks.
Figures to the right indicate full marks.
Use of log table and calculators in allowed.
Total Marks:70
SECTION I
Q.1 Answer the following: 14
What is a dielectric constant, and what information it provides?
In FT-NMR, how are nuclei excited?
The substance whose susceptibility is independent of temperature is
Why C12 and O16 nuclei do not react with the electron?
What is electronic polarisability?
Name the best known free radical used in calibrating ESR spectra?
The relationship between the relative permeability and the susceptibility is
Signals in a proton nmr spectrum provide information about the molecular mass of
an organic molecule. True False.
What is ferroelectricity?
For two equivalent protons, the number of lines in ESR spectrum are
Domains are present in diamagnetic materials. True False.
When the Mossbauer effect will occur?
What is the directional quantization?
Mossbauer effect is greater at lower temperature because it depends on
SECTION II
Q.2 Derive Clausius-Mossotti equation of molar polarization. 07
How crystal symmetry is understood using Mössbauer studies? 07
Q.3 At 27ºC, a coordinate compound (mol. Wt. 220 g mol-1) has density equal to 3.20
gcm-3. If it contains three unpaired electrons, calculate the molar magnetic
susceptibility and the magnetic susceptibility.
07
Applying Crystal field theory, derive the expression for molar magnetic
susceptibility in case of transition metal ion complexes.
07
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Q.4 Define the term coupling constant in NMR. Discuss the factors influencing
coupling constant.
07
Predict the ESR spectrum of the following radicals
ii) iii) Naphthalene C10H8

07
SECTION III
Q.5 Define paramagnetic susceptibility. How is it determined experimentally? 05
Distinguish between spin lattice and spin-spin relaxations. 05
Calculate the electronic polarizability of Argon atom.
(Given N 2.7 x 1025 atoms/m3 and 8.854 x 10-12
04
Q.6 How Gouy's balance is used for measuring the specific magnetic susceptibility? 05
What is quadruple splitting in Mossbauer spectroscopy? 05
Calculate the relative Boltzmann population of proton spins in the lower state to
that in the upper state in a magnetic field of flux density 1 T at room temperature.
What is the excess population in the lower state?
(Given: gN =5.585 and 5.05 x 10-27 J
04
Q.7 Write short notes on (any three) 14
Kramer's degeneracy
Curie Temperature
Double resonance technique
Doppler effect