Ammoniumiyhdisteitä

Ammonium compounds are inorganic and organic salts containing the ammonium cation, NH₄⁺, as the central positively charged species. They are formed when ammonia (NH₃) reacts with an acid, producing a salt in which the nitrogen atom is fully protonated. The ammonium cation can combine with a wide variety of anions, resulting in compounds such as ammonium chloride, ammonium sulfate, ammonium nitrate, ammonium carbonate, and numerous organoammonium salts.

These compounds are widely used in agriculture, where ammonium nitrate and ammonium sulfate serve as nitrogen fertilizers that provide essential nutrients for plant growth. In industry, ammonium salts find applications in the production of dyes, pharmaceuticals, plasticizers, and as reagents in analytical chemistry. Ammonium sulfate is also used as a food additive and a component of some laundry detergents. Ammonium metal complexes, particularly those containing transition metals, are employed as catalysts in polymerization and other organic transformations.

The production of many ammonium compounds involves the direct synthesis of ammonia via the Haber–Bosch process, followed by neutralization with acids such as hydrochloric or sulfuric acid. Ammonium salts can also be generated through ion‑exchange processes or by reacting ammonia with acids in aqueous solution. Because of their high solubility in water, ammonium salts are typically encountered as aqueous solutions in industrial settings.

From an environmental perspective, ammonia and ammonium compounds can contribute to nutrient loading in aquatic ecosystems, leading to eutrophication when excess nitrogen is introduced into water bodies. Management of ammonium waste in agricultural runoff is therefore an important consideration. Safety handling guidelines require ventilation in confined spaces, as high concentrations of ammonium chloride dust or gaseous ammonia can irritate the respiratory tract.