NH4OH=NH3+H2O is a decomposition chemical reaction. A decomposition-type reaction breaks one reactant into two or more products. In this case, ammonium hydroxide releases ammonia gas and water vapor when heated.
Ammonia hydroxide is also called alcali volatil or aqueous ammonia. It forms as a clear, colorless liquid with a pungent odor when ammonia gas dissolves in water.
Ammonia hydroxide requires care when used as a household cleaner. In concentrated form, it can burn skin on contact. When mixed with bleach, a mistake many people make, it releases chloramine vapor. Chloramine is a chemical warfare agent that was used in World War I because of its ability to collect in trenches and suffocate soldiers. If high enough concentrations of ammonia vapor are released when the bleach and aqueous ammonia are mixed, hydrazine may form and explode. Even if hydrazine doesn't explode, it can spray boiling liquid that is harmful to eyes and skin.
Ammonia hydroxide kills bacteria and leavens baked goods in commercial food production. It has a role in the manufacturing of fertilizer, plastic, rayon and rubber. Scientists have recently discovered that fuming ammonia hydroxide with cyanoacrylate, the main ingredient in superglues, produces nano-spheres that have medical applications in micro-filtering and drug delivery.