Here's why:

* Nitrogen's Electronic Configuration: Nitrogen has five valence electrons. In N₂, it forms a triple bond with another nitrogen atom, sharing three electron pairs.

* VSEPR Theory: According to the Valence Shell Electron Pair Repulsion (VSEPR) theory, electron pairs around a central atom repel each other and try to stay as far apart as possible.

* Linear Shape: In N₂, the two nitrogen atoms and the three shared electron pairs (triple bond) are all in a straight line, minimizing repulsion.

Therefore, nitrogen gas (N₂) has a linear molecular shape.