Manganese(II) chloride
4.png) molecular structure
|
|
_chloride_tetrahydrate.jpg) Tetrahydrate
|
|
| Names | |
|---|---|
|
IUPAC names
Manganese(II) chloride
Manganese dichloride |
|
| Other names
Manganous chloride
hyperchloride of managnese |
|
| Identifiers | |
7773-01-5  38639-72-4 (dihydrate) 13446-34-9 (tetrahydrate)
|
|
| 3D model (Jmol) | Interactive image |
| ChEMBL |
ChEMBL1200693 
|
| ChemSpider |
22888
|
| ECHA InfoCard | 100.028.972 |
| PubChem | 24480 |
| RTECS number | OO9625000 |
| UNII |
6YB4901Y90
|
|
|
|
|
| Properties | |
| MnCl2 | |
| Molar mass | 125.844 g/mol (anhydrous) 161.874 g/mol (dihydrate) 197.91 g/mol (tetrahydrate) |
| Appearance | pink solid (tetrahydrate) |
| Density | 2.977 g/cm3 (anhydrous) 2.27 g/cm3 (dihydrate) 2.01 g/cm3 (tetrahydrate) |
| Melting point | 654 °C (1,209 °F; 927 K) (anhydrous) dihydrate dehydrates at 135 °C tetrahydrate dehydrates at 58 °C |
| Boiling point | 1,225 °C (2,237 °F; 1,498 K) |
| 63.4 g/100 ml (0 °C) 73.9 g/100 ml (20 °C) 88.5 g/100 ml (40 °C) 123.8 g/100 ml (100 °C) |
|
| Solubility | soluble in pyridine, ethanol insoluble in ether |
| +14,350·10−6 cm3/mol | |
| Structure | |
| CdCl2 | |
| octahedral | |
| Hazards | |
| NFPA 704 | |
| Flash point | Non-flammable |
| Lethal dose or concentration (LD, LC): | |
|
LD50 (median dose)
|
250-275 mg/kg (rat, oral) 1715 mg/kg (mouse, oral) |
| Related compounds | |
|
Other anions
|
Manganese(II) fluoride Manganese(II) bromide Manganese(II) iodide |
|
Other cations
|
Manganese(III) chloride Technetium(IV) chloride Rhenium(III) chloride Rhenium(IV) chloride Rhenium(V) chloride Rhenium(VI) chloride |
|
Related compounds
|
Chromium(II) chloride Iron(II) chloride |
|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|
|
 (what is ?) |
|
| Infobox references | |
Manganese(II) chloride describes a series of compounds with the formula MnCl2(H2O)x, where the value of x can be 0, 2, or 4. The tetrahydrate is the most common form of "manganese(II) chloride" and is the tetrahydrate with the formula MnCl2·4H2O. The anhydrous form and a dihydrate MnCl2·2H2O are also known. Like many Mn(II) species, these salts are pink, with the paleness of the color being characteristic of transition metal complexes with high spin d5 configurations.
Manganese chloride is produced by treating manganese(IV) oxide with concentrated hydrochloric acid.
This reaction was once used for the manufacture of chlorine. By carefully neutralizing the resulting solution with MnCO3, one can selectively precipitate iron salts, which are common impurities in manganese dioxide.
In the laboratory, manganese chloride can be prepared by treating manganese metal or manganese(II) carbonate and hydrochloric acid:
Anhydrous MnCl2 adopts a layered cadmium chloride-like structure. The tetrahydrate consists of octahedral cis-Mn(H2O)4Cl2 molecules. The trans isomer, which is metastable, is also known. The dihydrate MnCl2(H2O)2 is a coordination polymer. Each Mn center is coordinated to four doubly bridging chloride ligands. The octahedron is completed by a pair of mutually trans aquo ligands.
The hydrates dissolve in water to give mildly acidic solutions with a pH of around 4. These solutions consist of the metal aquo complex [Mn(H2O)6]2+.
It is a weak Lewis acid, reacting with chloride ions to produce a series of solids containing the following ions [MnCl3]−, [MnCl4]2−, and [MnCl6]4−. Both [MnCl3]− and [MnCl4]2− are polymeric.
...
Wikipedia