Manganese(II) nitrate

Manganese(II) nitrate are the inorganic salts with formula Mn(NO3)2·(H2O)n. Each formula unit is composed of one Mn2+ cation and two NO3− anions and varying amounts of water. Most common is the tetrahydrate Mn(NO3)2·4H2O, but mono- and hexahydrates are also known as well as the anhydrous compound. Some of these compounds are useful precursors to the oxides of manganese.
Preparation, reactions, uses.
Manganese(II) nitrate is prepared by dissolving manganese(II) oxide in nitric acid:
It can also be prepared from manganese dioxide and nitrogen dioxide:
On heating to 300 °C, aqueous solutions of manganese(II) nitrate thermally decompose to form MnO2 and NO2.
Manganese(II) nitrate is the precursor to manganese carbonate, which is used in fertilizers and as a colorant. The advantage of this method, use of ammonia and carbon dioxide, being that the side product ammonium nitrate is also useful as a fertilizer.