Ammonium ion

Ammonium Ion

The ammonium ion (chemical formula: NH4+) is a positively charged polyatomic ion with the chemical formula NH4+. It is formed by the protonation of ammonia (NH3). Ammonium is also a general name for positively charged or cationic ammonia in the same way that hydron and hydroxide are names for H+ and OH−, respectively.

Formation

The ammonium ion is formed when an ammonia molecule gains a hydrogen ion (H+), which it readily does to increase its stability. This reaction is reversible, meaning that the ammonium ion can lose its extra hydrogen ion and revert back to ammonia.

Properties

Ammonium ions are found in a variety of salts such as ammonium carbonate, ammonium chloride, and ammonium nitrate. Most simple ammonium salts are very soluble in water. An exception is ammonium hexachloroplatinate, the formation of which was once used as a test of electronegativity.

Uses

Ammonium ions are a key component of many fertilizers, as they are a form of nitrogen that can be readily taken up by plants. They are also used in the production of ammonium nitrate for explosives and in the manufacture of ammonia-based cleaning products.

Health Effects

Exposure to high concentrations of ammonium ions can be harmful to humans and animals. They can cause irritation to the eyes, skin, and respiratory tract, and can lead to serious health problems if ingrown or inhaled in large amounts.

See Also

• Ammonia
• Ammonium nitrate
• Ammonium chloride
• Ammonium carbonate