Nitrogen Dioxide molecule
![Nitrogen Dioxide molecule](/sites/default/files/media/images/nitrogen_dioxide_no2_720x400.png)
UCAR (Randy Russell)
Four representations chemists use for nitrogen dioxide (NO2). Nitrogen dioxide is a gas that is found in small quantities in Earth's atmosphere. Nitrogen dioxide is a significant air pollutant in some areas. In the colored models of molecules, nitrogen is blue and oxygen is red.