NMR Spectroscopy MCQs : This section focuses on the "NMR Spectroscopy". These Multiple Choice Questions (MCQs) should be practiced to improve the NMR Spectroscopy skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
When placed in a magnetic field, all the random spins of the nuclei
A. stop
B. reverse direction
C. align with the magnetic field
D. rotate to 90° away from the induced field
Question 2
All hydrogen atoms
A. have the same resonance frequency
B. resonate at different frequencies depending on their environment.
C. are attached to carbon
D. resonate at about the same frequency as carbon
Question 3
What is used to cool the superconducting coil?
A. Hydrogen
B. Ice
C. Dry ice
D. Liquid helium
Question 4
Why is it important to use a deuterated solvent?
A. NMR uses least of this solvent
B. So the spectrometer can lock onto the sample to prevent the spectrum from drifting during aquisition
C. Expensive solvents work best with NMR
D. They dissolve polymer the fastest
Question 5
Coupling causes the peaks in 1H NMR spectra to be split into
A. two peaks
B. multiple peaks equal to the number of hydrogens on surrounding atoms
C. multiple peaks equal to the number of surrounding carbon atoms
D. multiple peaks equal to the number of hydrogen on surrounding atoms, plus one
Question 6
What is shielding in NMR?
A. Using a curved piece of metal to block an opponents attack
B. Putting metal around an Rf source
C. When the magnetic moment of an atom blocks the full induced magnetic field from surrounding nuclei
D. Blocking parts of a molecule from Rf radiation
Question 7
Better understanding of the nuclei is possible,
A. with the help of wavelength spectrum
B. with the help of frequencies ranges
C. with the help of a mathematical translator called the fourier transfer algorithm
D. none of the above
Question 8
NMR spectroscopy can be defined as an indispensable tool which applies a magnetic field to an atomic nucleus
A. TRUE
B. FALSE
Question 9
When molecules are placed in a strong magnetic field, the nuclei of some atoms will begin to behave like small magnets.
A. TRUE
B. FALSE
Question 10
The principle behind NMR is that many nuclei have spin and all nuclei are electrically charged.
A. TRUE
B. FALSE
Question 11
NMR spectroscopy cannot be used to study which of the following?
A. Interaction of protein with other molecules
B. Dynamic motion within proteins
C. Protein folding
D. Protein sequence
Question 12
Protein samples are now routinely enriched with which of the following isotopes to simplify the NMR data?
A. 1H and 31P
B. 31P and 15N
C. 1H and 15N
D. 13C and 15N
Question 13
The chemical shift of an atomic nucleus depends on its molecular environment and is different for each atom in a protein molecule.
A. False
B. True
Question 14
Three-dimensional structural information is obtained primarily from ‘through space’ NMR experiments involving the ‘nuclear Overhauser effect (NOE)’.
A. False
B. True
Question 15
What are the different frequencies obtained as NMR peaks called?
A. Chemical peaks
B. Biological shifts
C. Physical shifts
D. Chemical shifts
Question 16
Which of the following is a spectroscopic technique used to observe local magnetic fields around atomic nuclei?
A. Optical spectroscopy
B. Atomic spectroscopy
C. Massspectroscopy
D. NMR spectroscopy
Question 17
Which of the following is a technique for the determination of the three-dimensional structure of a protein?
A. Gas chromatography
B. Mass spectroscopy
C. Radiotherapy
D. NMR spectroscopy
Question 18
Which of the following is not a limitation of NMR spectroscopy?
A. Mostly used for small proteins (< 30 kDa)
B. Can only be used for proteins that are stable in solution
C. Problem arises with high frequencies (1000 MHz)
D. Cannot detect dynamic motion within proteins
Question 19
Which of the following is the definitive method to identify monomolecular organic compounds?
A. Mass spectroscopy
B. Infrared spectroscopy
C. X – ray crystallography
D. NMR spectroscopy
Question 20
Which of the following isotope is NMR inactive?
A. 1H
B. 13C
C. 31P
D. 16O
Question 21
Which of the following isotopes does not have a magnetic spin?
A. 1H and 15N
B. 1H and 16O
C. 12C and 31P
D. 12C and 16O
Question 22
Which of the following isotopes has a magnetic spin?
A. 16O
B. 12C
C. 14N
D. 31P
Question 23
Which of the following isotopes has a magnetic spin?
A. 12C
B. 16O
C. 14N
D. 15N
Question 24
Which of the following isotopes have a magnetic spin?
A. 2He and 13C
B. 2He and 12C
C. 1H and 12C
D. 1H and 13C