The only gas in group 15 is nitrogen (Nā‚‚).

Group 15 overview

Group 15 of the periodic table is also called the nitrogen family or pnictogens and includes nitrogen, phosphorus, arsenic, antimony, bismuth, and moscovium.

At standard temperature and pressure, nitrogen exists as a colorless, odorless diatomic gas, while the other common group 15 elements are solids.

Why only nitrogen is gaseous

  • Nitrogen forms very stable Nā‰”N molecules, giving it a low boiling point and gaseous state at room temperature.
  • Heavier group 15 elements have stronger intermolecular forces and higher melting and boiling points, so they are solids under normal conditions.

TL;DR: In the nitrogen family (group 15), nitrogen is the only element that is a gas under normal conditions.

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