Britannica Sources used in this answer

Which ammonium salts are used as nitrogen fertilizers?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Difference in molecular structure between ammonia/amines and quaternary ammonium ions — ammonia Ammonia and amines have a slightly flattened trigonal pyramidal shape with a lone pair of electrons above the nitrogen. In quaternary ammonium ions, this area is occupied by a fourth substituent.

Ammonia is a vital component in the production of synthetic fertilizers, often being converted into various ammonium salts to provide essential nitrogen for plant nutrition. The primary ammonium salts used as nitrogen fertilizers include:12

Ammonium nitrate (NH₄NO₃): A widely used fertilizer, it is produced by treating nitric acid with ammonia and is a common nitrogenous component in artificial fertilizers.134
Ammonium sulfate ((NH₄)₂SO₄): A colorless crystalline salt utilized primarily as a fertilizer.125
Ammonium phosphates: These compounds are also employed as sources of nitrogen in agricultural applications.12

While these salts are significant, it is worth noting that urea is the most commonly used nitrogen fertilizer worldwide due to its high nitrogen content and ease of conversion to ammonia within the soil.12