The rotationa l energy of a linear or spherical molecule with quantum number J is EJ = hBJ(J + 1 ). For a linear molecule. each rotational level has a degeneracy of (2J + 1 ). For a spherical molecule, the degeneracy is (2J + 1 )2 (a) Calculate the ratio of populations of CO2 molecules with J = 4 and J = 2 at 25 °C, given that the rotational constant of CO2 is B = 11.70 GHz. (b) Also calculate the ratio of populations of CH4 molecules with J = 4 and J = 2 at 25 °C, given that the rotational constant of CH4 is 157 GHz.

The rotationa l energy of a linear or spherical molecule with quantum number J is EJ = hBJ(J + 1 ). For a linear molecule. each rotational level has a degeneracy of (2J + 1 ). For a spherical molecule, the degeneracy is (2J + 1 )2 (a) Calculate the ratio of populations of CO2 molecules with J = 4 and J = 2 at 25 °C, given that the rotational constant of CO2 is B = 11.70 GHz. (b) Also calculate the ratio of populations of CH4 molecules with J = 4 and J = 2 at 25 °C, given that the rotational constant of CH4 is 157 GHz.

Physical Chemistry

2nd Edition

ISBN:9781133958437

Author:Ball, David W. (david Warren), BAER, Tomas

Publisher:Ball, David W. (david Warren), BAER, Tomas

Chapter2: The First Law Of Thermodynamics

Section: Chapter Questions

Problem 2.9E

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