Which of the following statements about the π molecular orbital description of cyclobutadiene is not correct?
A)Cyclobutadiene has two degenerate nonbonding π molecular orbitals.
B)Cyclobutadiene has a single bonding π molecular orbital.
C)Cyclobutadiene has two electrons in nonbonding π molecular orbitals.
D)Cyclobutadiene has one electron in an antibonding π molecular orbital which makes it antiaromatic.
E)none of the above

Question

Quizplus · Accepted Answer

This statement is incorrect. Cyclobutadiene has two degenerate bonding and antibonding π molecular orbitals. The four π electrons of cyclobutadiene would fit perfectly in the two bonding π molecular orbitals, resulting in a perfectly stable molecule. However, placing two electrons in the antibonding π molecular orbital would destabilize the molecule, making it antiaromatic. Therefore, cyclobutadiene is an example of an antiaromatic molecule.

Which of the Following Statements About the π Molecular Orbital