Basicity

Conversely, using a solvent system definition of acidity and basicity, water added to liquid ammonia functions as an acid, because it increases the concentration of the cation ammonium.

However, there is no strict trend in this regard, as basicity is also governed by other factors mentioned above.

Relative stabilization of methylammonium ions thus decreases with the number of methyl groups explaining the order of water basicity of methylamines.

Substituents on the aromatic ring, and their positions relative to the amine group may also considerably alter basicity as seen above.

The high basicity is attributed to the relief of strain upon protonation and strong internal hydrogen bonding.

These effects also decrease the basicity.