Ammonia is a gas which can decompose into hydrogen and nitrogen. It is colorless and has pungent odor. This substance has a number of features. First, ammonia is highly soluble, and therefore comes often and is used in dissolved form. For this reason, in the presence of hydrogen bond N...H-O and this gas forms a hydrate of ammonia, and exhibits the properties of a base.Hydrate of ammonia NH3*H2O is a liquid with white crystals and a characteristic odor. In its contact with the hydrochloric acid forms a white smoke.
To obtain a hydrate of ammonia, you must first get the ammonia. In the laboratory, obtaining ammonia is carried out by displacing it from NH4Cl, while it is heated with soda lime:
(with NaOH+CaO)
(in the presence of NaCl, CaCl, H2O).
In industry ammonia produced, restoring the nitrogen and hydrogen simultaneously at high temperature.
Hydrate of ammonia is formed due to hydrogen bonding of NH3...HOH. When boiled with concentrated NaOH hydrate decomposes into ammonia gas and water: NH3*H2O=NH3+H2O (in the presence of NaOH).
There are two types of solutions of this substance: dilute (3 to 10%) and concentrated (16 to 25 percent). Otherwise, the first solution is called liquid ammonia, and the second ammonia water.Ammonia is used in medicine, but it should be remembered that this solution is poisonous when it is improperly applied. Since ammonia has a considerable reactivity of a chemical transformation can be obtained a number of other substances, sometimes completely not similar to it in physical and chemical properties.
In the past ammonia was used as the refrigerant in the so-called absorption refrigerators. Currently such refrigerators are produced in a small and quiet designs, called mini-bars. Large refrigerators, with the aim of reducing the power consumption, today, almost universally translated into a compression system.