The illustrations below show s-s or p-p orbital overlaps. Identify the illustration that depicts a π bond based on the valence bond theory.

A.

B.

C.

D.

The following illustrations show the bond vibrations for the symmetric and asymmetric stretch in methane. Which vibration will cause IR radiation to be absorbed? Note that the arrows depict the movement of atoms during the vibration.

Give the illustration for two atoms that each has three 2p orbitals. Determine the number of bonding orbitals and the type of MO that can be constructed from the two sets of 2p orbitals. 

Draw the orbital diagram of OCl₂ without hybridization and highlight the bonding electrons. 

Draw the 3D representation of the molecule showing orbital overlap and identify the expected bond angle from the unhybridized orbitals. 

It was experimentally determined that the bond angle is 110.9°. 

What is the difference between the expected bond angle based on valence bond theory and the experimental measurement? 

Classify each of these molecular orbital representations as constructed from two s atomic orbitals or two p atomic orbitals.

HOMO is the abbreviation for the highest occupied molecular orbital of a molecule and LUMO is the abbreviation for the lowest unoccupied molecular orbital. The difference in energy between the HOMO and LUMO can be determined by taking the electronic absorption (UV-visible) spectrum of the molecule. The HOMO-LUMO transition corresponds to molecules going from their ground state to their first excited state. Identify the orbital transition that the lowest energy peak of O₂ corresponds to.

Which of the following statements is correct based on the given molecular orbital diagram for a six lithium atom chain?

a. There are no nodes in the lowest-energy unoccupied molecular orbital (LUMO)

b. There are 3 nodes in the lowest-energy unoccupied molecular orbital (LUMO)

c. There are 5 nodes in the lowest-energy unoccupied molecular orbital (LUMO)

d. There are 7 nodes in the lowest-energy unoccupied molecular orbital (LUMO)