Seneca
Sign up

Nitrogen & Ammonia

Chemistry: Cambridge International A Level, topic 2.5.1

Nitrogen & Ammonia

Nitrogen is an inert atmospheric gas. Ammonia is a basic nitrogenous compound with a variety of uses.

Nitrogen

Nitrogen

  • Nitrogen is a diatomic gas formed from two nitrogen atoms held together by a triple covalent bond.
  • The triple bond is very strong and difficult to break.
  • So, nitrogen is very unreactive (inert).
Ammonia and ammonium

Ammonia and ammonium

  • Ammonia (NH3 is a pyramidal compound with a lone pair of electrons.
  • The lone pair of electrons give ammonia basic properties.
  • Ammonia can act as a base and use its lone pair of electrons to accept a proton.
  • This how the ammonium ion (NH4+) is formed.
  • The type for covalent bond formed in this reaction is called a coordinate bond.
Ammonium salts

Ammonium salts

  • Ammonia is only a weak base. So, even though NH3 can accept an H+ ion, the H+ ion can be easily lost.
  • This can be represented by the following ionic equation:
  • NH3 + OH- ⇌ NH4+ + H2O
  • NH3 & NH4+ are called conjugate pairs.
  • So, when ammonium salts react with a base ammonia gas is evolved. For example:
  • NH4Cl + NaOH → NH3 + NaCl + H2O
Ammonia & ammonium

Ammonia & ammonium

Test yourself on Nitrogen & Ammonia

  • What type of covalent bond links nitrogen atoms in N2?

Practise this topic for free