B.Sc. III (Semester Entrepreneurship (Old CGPA) Examination, 2018
industrial chemistry
Spectroscopic Methods
Day and Date Thursday, 22-11-2018 Total Marks 70
Time 2.30 p.m. to 5.00 p.m.
Instructions All questions are compulsory.
Figures to the right indicate full marks.
Draw neat labeled diagrams wherever necessary.
1. Choose the correct alternative and rewrite the sentences again. 14
Reciprocal of wavelength is
Wave number Velocity
Frequency Electronic radiation
For linear molecule the number of fundamental modes of vibration is given
by
3N 3N 5 3N 6 3N 2
Higher δ values shows
upfield resonance downfield flipping
Methyl alcohol shows m/e peak at
30 32 36 40
Which type of electronic transition required highest energy
σ →
n → n →
The functional group region is in between
4000 1350 cm-1 2000 950 cm-1
4000 650 cm-1 1350 650 cm-1
Set P
SLR-SK 50 *SLRSK50*
Set P
The nuclei are having even mass number and atomic number is
in nature.
Magnetic Non magnetic
Neutral Positively charged
The Mass spectrum, the intensity assigned to base peak is
50% 60% 100%
Which of the following is Auxochrome
-NH2 -OH CH3 CH3
10) Among the following gives IR active transitions.
H2 N2 Cl2 HCl
11) In NMR Spectroscopy, δ is expressed in
cm-1 nm PPM Kg
12) In Mass spectroscopy, energy required for bombardment is ev.
50 60 80 70
13) Blue shift is know as shift.
Hyperchromic Hypochromic
Bathochromic Hypsochromic
14) IR spectroscopy is useful in determination of
Conjugation Molecular weight
Functional group None of these
2. Define and explain any four of the following 8
Define Hyperchromic shift and Hypochromic shift.
Calculate the modes of vibrations for non linear H2O molecule.
Define the term J value of first order reaction.
What do you mean by base peak
Explain equivalent and non equivalent protons.
Write short note on any two of the following. 6
Write the application of UV spectroscopy.
State different types of ions produced in Mass spectroscopy.
Explain the Shielding and Deshielding of a nucleus with suitable
example.
*SLRSK50* SLR-SK 50
Set P
3. Answer any two of the following 8
Explain types of vibration in IR spectroscopy.
Write the principles of PMR spectroscopy.
Discuss in detail the effect of conjugation on the position of UV bands
in dienes.
Answer any one of the following. 6
Explain the principle and diagram of Mass spectroscopy.
Draw a neat labeled diagram of NMR spectrometer and explain its
working.
4. Answer any two of the following 10
Calculate λmax of the following compound.
ii)
State and explain the mathematical expression of Hooke's law.
Write the application of NMR spectroscopy.
Answer any one of the following 4
How Mass spectroscopy can be used for determination of molecular
weight
State and explain Lambert's-Beer law with its mathematical
expression.
5. Answer any two of the following 14
Explain various transitions in UV spectroscopy.
Explain the principle of IR spectroscopy with schematic diagram of typical
double beam IR spectrophotometer.
Deduce the structure of following compound.
MF C7H8O
IR 3500 cm
PMR 3.7δ 4.4δ 7. 2δ 5H).