Ammonia solution, also known as ammonium hydroxide, ammonia water, ammonical liquor, ammonia liquor, aqua ammonia, aqueous ammonia, or simply ammonia, is a solution of ammonia in water. It can be denoted by the symbols NH₃(aq). Although the name ammonium hydroxide suggests a base with composition [NH₄⁺][OH^-], it is actually impossible to isolate samples of NH₄OH, as these ions do not comprise a significant fraction of the total amount of ammonia except in extremely dilute solutions.