Manganese(II) nitrate refers to the
inorganic compounds with
formula Mn(
NO3)
2·(H
2O)
n. These compounds are nitrate salts containing varying amounts of water. A common derivative is the tetrahydrate, Mn(NO
3)
2·4H
2O, 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.
Typical of a manganese(II) compound, it is a paramagnetic pale pink solid.
Structure
Manganese(II) compounds, especially with oxygenated ligands, are typically octahedral. Following this trend, the tetrahydrate features four
aquo ligand
In chemistry, metal aquo complexes are coordination compounds containing metal ions with only water as a ligand. These complexes are the predominant species in aqueous solutions of many metal salts, such as metal nitrates, sulfates, and perch ...
s bound to Mn as well as two mutually cis, unidentate nitrate
ligand
In coordination chemistry, a ligand is an ion or molecule ( functional group) that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's elec ...
s. The hexaaquo salt features octahedral
n(H2O)6sup>2+.
Preparation, reactions, uses
Manganese(II) nitrate is prepared from
manganese dioxide and
nitrogen dioxide
Nitrogen dioxide is a chemical compound with the formula . It is one of several nitrogen oxides. is an intermediate in the industrial synthesis of nitric acid, millions of tons of which are produced each year for use primarily in the productio ...
:
[
:MnO2 + 2 NO2 + 4H2O → Mn(H2O)4(NO3)2
Heating the tetrahydrate to 110 °C gives the pale yellow monohydrate.
The reaction is reversible in the sense that heating the dinitrate to 450°C gives a slightly nonstoichiometric dioxide.][
]
References
Manganese(II) compounds
Nitrates
{{inorganic-compound-stub