Born Oppenheimer Approximation - Physical Chemistry - Solved Problems, Exams of Physical Chemistry

Download Born Oppenheimer Approximation - Physical Chemistry - Solved Problems and more Exams Physical Chemistry in PDF only on Docsity!

KE Physical Chemistry I Name Exam II (Fall 2010) True/False (1 pt each). Please mark T for true and F for false: T 1, In the Born-Oppenheimer approximation, nuclei are treated as stationary while electrons move around them. E 2. A x molecular orbital has zero angular momentum about the internuclear axis. T 3. According to molecular orbital theory, the bond order of 0,” is one. - 4. The variational principle states that if an arbitrary wavefunction is used to calculate the energy, the value calculated is never greater than the true energy. FE 5. In the Huckel method, all overlap integrals Sj (i not equal to j) are one. T 6. Commutation may or may not hold for elements of a group, however the associative law must apply. T 7. AC; axis of rotation is associated with two different symmetry operations. Ee 8. Carbon tetrafluoride can be observed to have a pure rotational spectrum. T 9. In a Coy molecule, x-polarized light will allow the A; to By transition. F 10. The lowest energy Huckel orbital of benzene is of A; symmetry (this orbital is constructed from 6 p; orbitals all with positive coefficients). Short answer (5 points each) 11. Write the ground-state electron configuration and bond order for the N,? ion. Would this ion have a longer or shorter bond length than the neutral molecule? 2 QR, 4A, a 2 (Sas) Gad) ep) (Top) (Bend beer AR Lowe than No 12. Write down the Huckel determinant for methylene cyclopropene, qf i Zz 4