Question

study the following sketch of a molecular orbital (mo) in a homonuclear diatomic molecule. this mo was formed by combining one 2p atomic orbital from each atom. the dark dots in this sketch are the nuclei. now use the sketch to complete the table below. write the symbol for this mo. is this a bonding or antibonding mo? what is the energy of this mo, compared to the energy of a 2p orbital on one of the separate atoms?

Explanation:

Step1: Identify MO symbol

When two 2p - atomic orbitals combine in a way that there is a nodal - plane perpendicular to the internuclear axis and passing through the nuclei, it is a $\pi$ molecular orbital. So the symbol is $\pi$.

Step2: Determine bonding or antibonding

In a bonding $\pi$ - molecular orbital, the electron density between the nuclei is non - zero. In an antibonding $\pi$ - molecular orbital, there is a nodal plane between the nuclei. Since there is a nodal plane between the nuclei in the given sketch, it is an antibonding MO.

Step3: Compare energy

Antibonding molecular orbitals have higher energy than the atomic orbitals from which they are formed. So the energy of this MO is higher than the energy of a 2p orbital on one of the separate atoms.

Answer:

Property	Answer
Is this a bonding or antibonding MO?	antibonding
What is the energy of this MO, compared to the energy of a 2p orbital on one of the separate atoms?	higher