Nitric Oxide (NO) is a colorless, nonflammable gas that readily reacts with oxygen to form nitrogen dioxide at room temperature. It is highly toxic and is obtained by the high temperature oxidation of ammonia. Its main usage is as an inert atmosphere in electrical systems.
| Molecular weight: 30.01 | Critical temperature: 180 K |
| Melting point: 109.6 K | Critical pressure: 6.48 MPa |
| Boiling point: 121.4 K | Critical density: 517 kg/m3 |
| Normal vapor density: 1.34 kg/m3 | (@ 0°; 101.3 kPa) |