Nitrogen

Nitrogen is a chemical element with symbol N and atomic number 7. It is the lightest pnictogen and at room temperature, it is a transparent, odorless diatomic gas. Nitrogen is a common element in the universe, estimated at about seventh in total abundance in the Milky Way and the Solar System. On Earth, the element forms about 78% of Earth's atmosphere and is the most abundant uncombined element. The element nitrogen was discovered as a separable component of air by Scottish physician Daniel Rutherford in 1772.