Nitrogen is the chemical element with the symbol N and atomic number 7. It was first discovered and isolated by Scottish physician Daniel Rutherford in 1772. Nitrogen is the lightest member of group 15 of the periodic table, often called the pnictogens. It is a common element in the universe, estimated at seventh in total abundance in the Milky Way and the Solar System.

Pnictogens and Chalcogens

A pnictogen is one of the chemical elements in group 15 of the periodic table. This group is also known as the nitrogen family. The chalcogens are the chemical elements in group 16 of the periodic table. This group is also known as the oxygen family.

Pnictogens consist of the elements nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), bismuth (Bi),  and perhaps the chemically uncharacterized synthetic element moscovium (Mc).