The appropriate value in blank given is Δf = 5.5 x
Hertz.
We have vibrational - rotational spectrum Hydrochloric Acid.
We have to investigate the estimated separation between absorption peaks and fill the blank.
<h3>What is vibrational - rotational spectrum ?</h3>
Rotational–vibrational spectroscopy is a branch of molecular spectroscopy. It deals with the infrared and Raman spectra of molecules in the gaseous phase.
According to the question -
The estimated separation between absorption peaks in the vibrational-rotational spectrum of HCl is denoted by Δf and is equal to -
Δf = 5.5 x
Hertz
Hence, the appropriate value in blank given is Δf = 5.5 x
Hertz.
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