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)
Chemical chameleon Chemical chameleon The chemical chameleon is a redox reaction, well known from classroom demonstrations, that exploits the dramatic color changes associated with the various oxidation states of manganese. Glauber reported the first description of the production of potassium permanganate when he noted that manganese dioxide (as the mineral pyrolusite) could be reacted at high temperatures with alkali to obtain a material that dissolved in water to give a green solution which slowly shifted to a violet-red. This process, similar to that still used in the production of potassium permanganate, oxidized manganese dioxide to potassium manganate which, acidified by carbon dioxide