Manganese(II) nitrate Manganese(II) nitrate Manganese(II) nitrate are the inorganic compounds with formula Mn(NO)(HO). Each formula unit is composed of one Mn cation and two NO anions and varying amounts of water. Most common is the tetrahydrate Mn(NO)·4HO, 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. 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 MnO and NO. Manganese(II)
Manganese recovery of the manganese. For further purification, the manganese can then be sent to an electrowinning facility. In 1972 the CIA's Project Azorian, through billionaire Howard Hughes, commissioned the ship "Hughes Glomar Explorer" with the cover story of harvesting manganese nodules from the sea floor. That triggered a rush of activity to collect manganese nodules, which was not actually practical. The real mission of "Hughes Glomar Explorer" was to raise a sunken Soviet submarine, the K-129, with the goal of retrieving Soviet code books. Manganese has no satisfactory substitute in its major applications in metallurgy. In minor applications, (e.g., manganese