Ammonia (NH3):

This is the only thermodynamically stable nitrogen hydride.

It is prepared by the Haber process:

Ammonia has a pyramidal structure, which undergoes rapid inversion (at a rate of 1010 s-1)

Ammonia is more soluble in water than any other gas. This is due to the formation of H-bonds between the NH3 and H2O molecules. It dissolves to give a basic solution. As well as being a Bronsted base (proton-acceptor), it is also a Lewis base (electron pair donor), and forms complexes with Transition Metal ions with its lone pair acting as a σ-donor.

Reactivity

Liquid ammonia is used as a non-aqueous solvent, although its self ionization is weaker than in water.Other properties

Hydrazine (N2H4):

Hydrazine has a 100% gauche structure at   25 oC, and is unstable with respect to formation of N2 and 2H2

This is a weaker base than ammonia, but it is dibasic.

It acts as a strong reducing agent, eg. in the Wolff-Kishner reduction, the driving force being the formation of the strong triple bond in N2.

Di-Imide (N2H2):

This is unstable and has the cis-structure.

Hydrazoic acid (HN3):

The azide anion (N3) is linear (N=N+=N), symmetric and a stable leaving group.