The moment of inertia of CH4 can be calculated from the expression I=8/3 mHR2 where R is the C-H bond length (109 angstrom or 109 x 1012 m). a. What is the lowest possible rotational energy of the CH4 molecule and what is the value of quantum number l associated with that rotational energy? b. Calculate the rotational energy of the molecule in the first excited state (when quantum number l = 1). c. Determine the degeneracy of the first excited state. Explain what is meant by rotational energy degeneracy.

The moment of inertia of CH4 can be calculated from the expression I=8/3 mHR2 where R is the C-H bond length (109 angstrom or 109 x 1012 m). a. What is the lowest possible rotational energy of the CH4 molecule and what is the value of quantum number l associated with that rotational energy? b. Calculate the rotational energy of the molecule in the first excited state (when quantum number l = 1). c. Determine the degeneracy of the first excited state. Explain what is meant by rotational energy degeneracy.

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Chapter20: Molecular Spectroscopy And Photochemistry

Section: Chapter Questions

Problem 14P

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