FT IR Spectroscopy
When radiation energy is absorbed by a spin 1/2 nucleus in a magnetic field, what happens?

The angle of precession flips so that the magnetic moment of the nucleus opposes the applied field
The processional frequency of the nucleus increases
None of these
The nucleus spins faster

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FT IR Spectroscopy
Why is it advantageous to record many FID signals from the same sample and then add them together?

To remove inaccuracies caused by fluctuations in the applied magnetic field
None of these
To ensure that all target nuclei in the sample have been excited
To increase sensitivity

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FT IR Spectroscopy
What does the Michelson interferometer do?

Modulate the I.R. signal at a lower frequency, so that it can be observed by a detector
Selectively filter certain wavelengths from a beam of I.R. radiation
Split a polychromatic beam of radiation into its component wavelengths
None of these

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FT IR Spectroscopy
What is meant by rotating frame of reference?

None of these
That the sample is spun rapidly in the applied field
That the detector rotates around the sample
If the laboratory itself is imagined to be rotated at the Larmor frequency, viewing that individual magnetic moment vectors are fixed in space

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