Principles of Instrumental Analysis
7th Edition
ISBN: 9781305577213
Author: Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher: Cengage Learning
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Question
Chapter 16, Problem 16.2QAP
Interpretation Introduction
(a)
Interpretation:
The force constant for
Concept introduction:
The force constant is defined as the restoring force divide by unit distance by which the bond is stretched out. The force constant is used for the analysis and characteristics of the molecules.
Interpretation Introduction
(b)
Interpretation:
The wavenumber of the absorption band for
Concept introduction:
The wavenumber is defined as the wavelength per unit distance. The wavenumber is generally expressed in
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(a) Draw a rough schematic of the series of resonances corresponding to a vibrational transition
for a diatomic. Label the P and R branches, explain what the difference is between them, and
indicate what the spacing is between the resonance lines.
(b) What is the main information about a diatomic molecule that one can obtain from vibrational
and rotational transition frequencies (assuming that the reduced mass is known)?
(b) The UV-visible electronic absorbance spectrum of the following azo dye has
an absorption maximum at 524 nm.
Three Raman excitation wavelengths are available to obtain the spectrum of
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Explain as fully as possible, the differences in the spectra that would be
expected using each of these different excitation wavelengths, and why
differences occur. State which wavelength would be the most appropriate,
justify your answer.
NH2
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OMe
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N-NH
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The hydrogen hal ides have the following fundamental vibrational wavenumbers: HF HCI HBr HIv/cm-1 4138 2992 2649 2308(a) Calculate the force constants of the hydrogen-halogen bonds. (b) Predict the fundamental vibrational wavenumbers of the deuterium hal ides.
Chapter 16 Solutions
Principles of Instrumental Analysis
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