Like water, liquid NH₃ is an associated solvent through extensive hydrogen bonding. However, due to the lower electronegative of nitrogen as compared to oxygen, ammonia molecules are less strongly associated than H-O-H molecules in water. The O-H...O hydrogen bond is stronger than the N-H..N bond. Also hydrogen bonding in liquid NH₃ cannot form cross-linked network since each NH₃ molecule has only 1 lone pair of electrons compared with 2 for each H₂O molecule. It is because of weaker hydrogen bonding in liquid NH₃ that it has the lower mp , bp, density, viscosity, dielectric constant and electric conductivity.

Due to weaker hydrogen bonding in liquid NH₃ (than in liquid H₂O), the freezing point and boiling point of liquid. NH₃ are lower than those of water. The liquid range in ammonia is only between (-77.7 to -33.4 ⁰C, i.e., ≈ 44 ⁰C) as compared to that of water which ranges between 0 to 100⁰C. The small liquid range creates a few handling problems. Its high heat of vaporization makes it way to handle in simple vacuum flasks without rapid bonding of the ammonia.

 The dielectric constant of ammonia (22 at – 33.4⁰C) is much lower as compared to that of water (81 at 18⁰C), suggesting that ammonia is a poor solvent for ionic substances. Generally, ammonium salts of large uninegative ions such as nitrates (NO₃^-), thiocyantes (SCN^-) and iodides (I^-) are soluble in liquid ammonia.

 Liquid ammonia has lower viscosity (0.254 at – 33.4⁰C) than that of water (0.959 cP at 25⁰C). This suggests that liquid ammonia provides less resistance towards the mobilities of ions. Therefore, ions of soluble salts have greater ionic mobility in liquid NH₃ than in water. This compensates for its having lower dielectric constant value.

The extent of self-ionization in ammonia is much les than in water.

2NH₃  <==>  NH₄⁺ + NH₂^-            K = 1.0 X 10^-33 (-40⁰C)
2H₂O  <==>  H₃O⁺ + OH^-               K = 1.0 X 10^-14 (25⁰C)

It shows that ammonia conducts current to a very limited extent and is a better solvent for covalent substances.  

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