Welcome to the Quiz!
This quiz contains 10 questions from a mix of 1 subtopics.
What is the main purpose of NMR spectroscopy?
to measure the melting point of a substance
to identify the functional groups present in a molecule
to determine the molecular weight of compounds
to understand the structure of molecules
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What characteristic do atomic nuclei with an odd total number of protons and electrons exhibit?
nuclear spin
nuclear fission
nuclear decay
nuclear fusion
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Which alignment of nuclei corresponds to a state of lower energy?
independent of the external magnetic field
anti-parallel to the external magnetic field
parallel to the external magnetic field
perpendicular to the external magnetic field
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What does the term chemical environment refer to in NMR spectroscopy?
all atoms, functional groups, and bonds directly connected to the nucleus
the solvent used to dissolve the sample
the temperature of the sample during analysis
the external magnetic field applied to the sample
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What is the common reference standard used in NMR spectroscopy?
dimethyl sulfoxide (DMSO)
chloroform (CHCl3)
benzene (C6H6)
tetramethylsilane (TMS)
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What does the chemical shift (δ) represent in NMR spectroscopy?
the difference in absorption frequency relative to the TMS peak
the number of peaks in the NMR spectrum
the width of the NMR peaks
the intensity of the NMR signal
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What do chemical shift values towards higher frequencies indicate?
(Select all that apply).
peaks moving towards the right on the NMR spectrum
peaks corresponding to nuclei with decreased shielding by surrounding electrons
peaks moving towards the left on the NMR spectrum
peaks corresponding to nuclei with increased shielding by surrounding electrons
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Nuclei situated in different chemical environments will be to varying degrees, leading them to absorb waves at slightly different frequencies and energies.
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In NMR spectroscopy, the chemical shift is expressed in units of {A}.
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The chemical shift value of a peak in a 1H NMR spectrum is measured in...
wavelength (λ)
hertz (Hz)
megahertz (MHz)
parts per million (ppm)
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