Engineering Chemistry MCQ (Molecular Spectroscopy)

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Engineering Chemistry MCQ (Molecular Spectroscopy)

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1. The different types of energies associated with a molecule are __________
a) Electronic energy
b) Vibrational energy
c) Rotational energy
d) All of the mentioned
Answer: d
Explanation: The different types of energies associated with a molecule are
electronic energy, vibrational energy, rotational energy and translational energy.

2. During the motion, if the centre of gravity of molecule changes, the molecule possess __________
a) Electronic energy
b) Rotational energy
c) Translational energy
d) Vibrational energy
Answer: c
Explanation: During the motion, if the centre of gravity of molecule changes, the
molecule possess translational energy. Translational refers to the movement in
horizontal or vertical direction.

3. The correct order of different types of energies is __________
a) Eel >> Evib >> Erot >> E tr
b) Eel >> Erot >> Evib >> E tr
c) Eel >> Evib >> Etr >> E rot
d) Etr >> Evib >> Erot >> E el
Answer: a
Explanation: The correct order is: Eel >> Evib >> Erot >> E tr. Electronic enrgy is the
highest whereas translational energy is the lowest.

4. The region of electromagnetic spectrum for nuclear magnetic resonance is __________
a) Microwave
b) Radio frequency
c) Infrared
d) UV-rays
Answer: b
Explanation: The region of the electromagnetic spectrum for nuclear magnetic
resonance is radio frequency.

5. Which of the following is an application of molecular spectroscopy?
a) Structural investigation
b) Basis of understanding of colors
c) Study of energetically excited reaction products
d) All of the mentioned
Answer: d
Explanation: The various applications of molecular spectroscopy are- Structural
investigation, basis of understanding of colors and study of energetically excited reaction products.

6. Select the correct statement from the following option.
a) Spectroscopic methods require less time and more amount of sample than classical methods
b) Spectroscopic methods require more time and more amount of sample than classical methods
c) Spectroscopic methods require less time and less amount of sample than classical methods
d) Spectroscopic methods require more time and less amount of sample than classical methods
Answer: c
Explanation: Spectroscopic methods require less time and less amount of sample
than classical methods (1 mg).

7. The results obtained by spectroscopic methods are less reliable, less reproducible and incorrect than classical methods.
a) True
b) False
Answer: b
Explanation: The results obtained by spectroscopic methods are reliable,
reproducible and correct than classical methods.

8. The transition zone for Raman spectra is __________
a) Between vibrational and rotational levels
b) Between electronic levels
c) Between magnetic levels of nuclei
d) Between magnetic levels of unpaired electrons
Answer: a
Explanation: The transition zone for Raman spectra is between vibrational and
rotational levels. Raman spectroscopy is a spectroscopic technique used to observe
vibrational, rotational, and other low-frequency modes in a system.

9. The criteria for electronic spin resonance is ____________
a) Periodic change in polarisability
b) Spin quantum number of nuclei > 0
c) Presence of unpaired electron in a molecule
d) Presence of chromophore in a molecule
Answer: c
Explanation: The criterion for electronic spin resonance is the presence of unpaired
electron in a molecule. This spectroscopy is a method for studying materials with unpaired electrons.

10. Sample recovery is possible after spectroscopic analysis because the sample is not chemically affected.
a) True
b) False
Answer: a
Explanation: Sample recovery is possible after spectroscopic analysis because the
sample is not chemically affected.