Nitrogen
Nitrogen (氮, symbol N) is chemical element number 7, a Reactive Nonmetal in period 2, group 15 of the periodic table, with a standard atomic weight of about 14.007. Comprises 78% of Earth's atmosphere. Essential for proteins and DNA.
Properties
| Atomic number | 7 |
|---|---|
| Symbol | N |
| Atomic mass | 14.007 u |
| Category | Reactive Nonmetal |
| Period | 2 |
| Group | 15 |
| Electron configuration | [He] 2s² 2p³ |
| Electronegativity | 3.04 |
| Covalent radius | 71 pm |
| Density | 0.001251 g/cm³ |
| Melting point | 63.15 K |
| Boiling point | 77.36 K |
| Discovery | Daniel Rutherford, 1772 |
Overview
Comprises 78% of Earth's atmosphere. Essential for proteins and DNA. Nitrogen (N) holds position 7 in the periodic table, a Reactive Nonmetal in period 2, group 15. As a nonmetal it tends to gain electrons, or to share them with other nonmetals when bonding.
With 5 electrons in its outermost shell, Nitrogen bonds accordingly; full configuration [He] 2s² 2p³, electronegativity 3.04. At room temperature it is normally a gas (a very low melting point); it melts near 63.15 K (-210 °C), boils near 77.36 K (-195.8 °C), has a density around 0.001251 g/cm³.
Common applications range across Agriculture / Fertiliser and Industrial Gas. Compounds featured on this site include HNO₃ and NH₃. It was first described by Daniel Rutherford in 1772. See more trends in the visualization center.
Electron shells
Electrons per shell: 2 · 5
Main uses
- Agriculture / Fertiliser
- Industrial Gas
Hazard
Compounds containing Nitrogen
Data sources
Atomic mass uses IUPAC (CIAAW) standard atomic weights; the covalent radius is from Cordero et al. (2008). Verify on the RSC Periodic Table, PubChem and Wikipedia. Educational reference only.