Question

How many antibonding orbitals are in nitrogen gas, `N_2`?

Answer 1

There are five antibonding orbitals in a molecule of N₂.

The lowest energy orbital is the `σ^✳`(1s) orbital. This is not a valence-shell orbital.

The lowest energy antibonding orbital in the valence shell is the `σ^✳`(2s) orbital. Then come two degenerate and unfilled `π^✳`(2p) orbitals. Finally, the highest energy orbital is the `σ^✳`(2p) orbital.