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

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

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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
To ensure that all target nuclei in the sample have been excited
To increase sensitivity
None of these

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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
Split a polychromatic beam of radiation into its component wavelengths
Selectively filter certain wavelengths from a beam of I.R. radiation
None of these

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FT IR Spectroscopy
In scanning electron microscopy

a specimen is fixed and then coated with transition metal
a specimen is fixed and then coated with thin layer of a heavy metal
a specimen is not fixed and then coated with thin layer of a heavy metal
None of these

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FT IR Spectroscopy
In FT-NMR, how are nuclei excited?

By an intense pulse of radiation which contains a wide range of frequencies
None of these
By an intense pressure
By radio-frequency radiation whose frequency is swept across a predetermined range

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