Nitrogen

Properties

Atomic number

7

Atomic mass

14.007 u

Category

Reactive Nonmetal

Group

15

Period

2

Block

p-block

Electron configuration

[He] 2s² 2p³

Phase at STP

Gas

Density

1.251 g/L

Melting point

63.15 K (-210.0 °C)

Boiling point

77.36 K (-195.8 °C)

Electronegativity

3.04

Atomic radius

56 pm

Ionization energy

14.534 eV

Discovery

1772 · Daniel Rutherford

Compounds you can make with nitrogen

Nitrogen appears in 11 compounds in our periodic table sandbox. Each one is a real substance with its true chemical formula — combine the right elements in the right ratio below to discover it.

• NH₃

  Ammonia

  A sharp-smelling gas, the backbone of nitrogen fertilizers that feed the world.

• N₂

  Nitrogen Gas

  The inert gas that makes up most of the air we breathe.

• HNO₃

  Nitric Acid

  A powerful acid used to make fertilizers and explosives.

• NO₂

  Nitrogen Dioxide

  A reddish-brown gas that gives smog its color and contributes to acid rain.

• NH₄Cl

  Ammonium Chloride

  A salt used in batteries, fertilizer, and as a food additive (salty licorice).

• N₂O

  Nitrous Oxide (Laughing Gas)

  Laughing gas — a mild anesthetic and the propellant in whipped cream.

• KNO₃

  Potassium Nitrate (Saltpeter)

  Saltpeter, an oxidizer in gunpowder, fertilizer, and food curing.

• NaNO₃

  Sodium Nitrate (Chile Saltpeter)

  A nitrogen-rich salt mined in deserts, used as fertilizer and a food preservative.

• NH₄NO₃

  Ammonium Nitrate

  A high-nitrogen fertilizer that is also a powerful industrial explosive.

• AgNO₃

  Silver Nitrate

  A light-sensitive silver salt used in photography, mirrors, and antiseptics.

• HCN

  Hydrogen Cyanide (Prussic Acid)

  A fast-acting poison with a faint almond smell, used industrially in tiny amounts.

Try it yourself: the nitrogen sandbox