Interpretation:
The difference in the way a CW and an FT-NMR experiment is performed should be stated.
Concept Introduction:
Nuclear magnetic resonance is a technique that is used to predict the structural formula of the compound. NMR spectroscopy involves the examination of the nucleus under the external magnetic field.
Answer to Problem 19.1QAP
The CW spectometer scans a range of frequencies at a time while the FT-NMR scans all the frequencies. The plot between signal intensity and frequency is observed in CW experiment while the plot between signal and time is changed into the plot of signal and frequency by fourier transform.
Explanation of Solution
FT-NMR and CW corresponds to fourier transform nuclear magnetic resonance and continuous wave respectively.
In CW experiment, scanning of the sample is done by the spectrometer. It scans a range of frequencies. The interrogation of the sample takes place with one frequency at a time. The plot between signal intensity and frequency is observed as the frequency range is scanned.
In the FT-NMR experiment, the interrogation of the sample takes place with the range of frequencies. All the frequencies are interrogated at once. The decay of signal takes place with respect to time and it is observed as free induction decay. The plot between signal and time is changed into the plot of signal and frequency by fourier transform.
The CW spectometer scans a range of frequencies at a time while the FT-NMR scans all the frequencies. The plot between signal intensity and frequency is observed in CW experiment while the plot between signal and time is changed into the plot of signal and frequency by fourier transform.
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Chapter 19 Solutions
Principles of Instrumental Analysis
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