Manganese(II) chloride

ball-and-stick model of crystal packing

molecular structure

Tetrahydrate

Names
IUPAC names

Manganese(II) chloride
Manganese dichloride

Other names

Manganous chloride
hyperchloride of manganese

Identifiers

CAS Number

* 7773-01-5 Y
* 20603-88-7 (dihydrate) N
* 13446-34-9 (tetrahydrate) Y

3D model (JSmol)

* Interactive image

ChEMBL |

* ChEMBL1200693 N

ChemSpider |

* 22888 Y

PubChem CID

* 24480

RTECS number |

* OO9625000

UNII |

* 6YB4901Y90 Y
* QQE170PANO (tetrahydrate) Y

InChI

* InChI=1S/2ClH.Mn/h2*1H;/q;;+2/p-2 Y

Key: GLFNIEUTAYBVOC-UHFFFAOYSA-L Y

* InChI=1S/2ClH.Mn/h2*1H;/q;;+2/p-2

Key: GLFNIEUTAYBVOC-NUQVWONBAP

* Key: GLFNIEUTAYBVOC-UHFFFAOYSA-L

SMILES

* Cl[Mn]Cl

Properties

Chemical formula

| 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)

Solubility in water

| 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 | slightly soluble in pyridine, soluble in ethanol
insoluble in ether

Magnetic susceptibility (χ)

| +14,350·10−6 cm3/mol
Structure

Crystal structure

| CdCl2

Coordination geometry

| octahedral
Hazards
NFPA 704 (fire diamond)  |

Flash point | Non-flammable
Lethal dose or concentration (LD, LC):

LD50 (median dose)

| 250-275 mg/kg (rat, oral)[citation needed]
1715 mg/kg (mouse, oral)[1]
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).

N verify (what is YN ?)
Infobox references

Manganese(II) chloride is the dichloride salt of manganese, MnCl2. This inorganic chemical exists in the anhydrous form, as well as the dihydrate (MnCl2·2H2O) and tetrahydrate (MnCl2·4H2O), with the tetrahydrate being the most common form. 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.[2]

## Contents

* 1 Preparation
* 1.1 Structures
* 2 Chemical properties
* 2.1 Magnetism
* 3 Natural occurrence
* 4 Precautions
* 5 References
* 6 External links

## Preparation

Manganese chloride is produced by treating manganese(IV) oxide with concentrated hydrochloric acid.

MnO2 \+ 4 HCl → MnCl2 \+ 2 H2O + Cl2

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.[3]

Sample of anhydrous MnCl2.

In the laboratory, manganese chloride can be prepared by treating manganese metal or manganese(II) carbonate with hydrochloric acid:

Mn + 2 HCl + 4 H2O → MnCl2(H2O)4 \+ H2
MnCO3 \+ 2 HCl + 3 H2O → MnCl2(H2O)4 \+ CO2

### Structures

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.[4][5] 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.[6]

Subunit of MnCl2(H2O)2 lattice.

## Chemical properties

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 salts containing the following ions [MnCl3]−, [MnCl4]2−, and [MnCl6]4−.

Upon treatment with typical organic ligands, manganese(II) undergoes oxidation by air to give Mn(III) complexes. Examples include [Mn(EDTA)]−, [Mn(CN)6]3−, and [Mn(acetylacetonate)3]. Triphenylphosphine forms a labile 2:1 adduct:

MnCl2 \+ 2 Ph3P → [MnCl2(Ph3P)2]

Anhydrous manganese(II) chloride serves as a starting point for the synthesis of a variety of organomanganese compounds. For example, manganocene is prepared by reaction of MnCl2 with a solution of sodium cyclopentadienide in tetrahydrofuran (THF).

MnCl2 \+ 2 NaC5H5 → Mn(C5H5)2 \+ 2 NaCl

Similar reactions are used in the preparation of the antiknock compound methylcyclopentadienyl manganese tricarbonyl.[3]

Manganese chloride is a precursor to organomanganese reagents in organic chemistry.[7][8]

Manganese chloride is mainly used in the production of dry cell batteries.

### Magnetism

Manganese(II) salts are paramagnetic. As such the presence of such salts profoundly affect NMR spectra.[9]

## Natural occurrence

Scacchite is the natural, anhydrous form of manganese(II) chloride.[10]

## Precautions

Manganism, or manganese poisoning, can be caused by long-term exposure to manganese dust or fumes.

## References

1. ↑ "Manganese compounds (as Mn)". Immediately Dangerous to Life and Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH). https://www.cdc.gov/niosh/idlh/7439965.html.
2. ↑ N. N. Greenwood, A. Earnshaw, Chemistry of the Elements, 2nd ed., Butterworth-Heinemann, Oxford, UK, 1997.
3. ↑ 3.0 3.1 Reidies, Arno H. (2002), "Manganese Compounds", Ullmann's Encyclopedia of Industrial Chemistry, Weinheim: Wiley-VCH, doi:10.1002/14356007.a16_123, ISBN 978-3-527-30385-4 .
4. ↑ Zalkin, Allan; Forrester, J. D.; Templeton, David H. (1964). "Crystal structure of manganese dichloride tetrahydrate". Inorganic Chemistry 3 (4): 529–33. doi:10.1021/ic50014a017. http://www.escholarship.org/uc/item/7vf7p79j.
5. ↑ A. F. Wells, Structural Inorganic Chemistry, 5th ed., Oxford University Press, Oxford, UK, 1984.
6. ↑ Morosin, B.; Graeber, E. J. (1965). "Crystal structures of manganese(II) and iron(II) chloride dihydrate". Journal of Chemical Physics 42 (3): 898–901. doi:10.1063/1.1696078. Bibcode: 1965JChPh..42..898M.
7. ↑ Gérard Cahiez, François Chau, Bernard Blanchot (1999). "Regioselective Monoalkylation of Ketones Via Their Manganese Enolates: 2-Benzyl-6-Methylcyclohexanone from 2-Methylcyclohexanone". Organic Syntheses 76: 239. doi:10.15227/orgsyn.076.0239.
8. ↑ S. Marquais, M. Alami, and G. Cahiez (1995). "Manganese-Copper-Catalyzed Conjugate Addition of Organomagnesium Reagents to a,b-Ethylenic Ketones\: 2-(1,1-Dimethylpentyl)-5-methyl-cyclohexanone from Pulegone". Organic Syntheses 72: 135. doi:10.15227/orgsyn.072.0135.
9. ↑ Frohlich, Margret; Brecht, Volker; Peschka-Suss, Regine (January 2001), "Parameters influencing the determination of liposome lamellarity by 31P-NMR", Chemistry and Physics of Lipids 109 (1): 103–112, doi:10.1016/S0009-3084(00)00220-6, PMID 11163348
10. ↑ "Scacchite". https://www.mindat.org/min-3549.html.

## External links

* National Pollutant Inventory: Manganese and compounds Fact Sheet

* v
* t
* e

Manganese compounds

* MnO
* Mn3O4
* Mn5O8
* MnS
* MnS2
* MnSO4
* MnSe2
* MnSe
* MnTe
* Mn(NO3)2
* MnCO3
* MnCl2
* MnCl3
* MnCl4
* MnF2
* MnBr2
* MnI2
* MnTiO3
* MnMoO4
* Mn(CH3COO)2
* Mn2O3
* MnF3
* K6Mn2O6
* MnO2
* Mn(OH)2
* MnO3
* K3MnO4
* MnF4
* Na2MnO4
* K2MnO4
* Mn2O7
* NaMnO4
* KMnO4
* NH4MnO4
* AgMnO4
* Ca(MnO4)2
* Ba(MnO4)2
* MnH(CO)5
* Mn2(CO)10

* v
* t
* e

Salts and covalent derivatives of the chloride ion

HCl |  |  |  | He

|
|
|
|

LiCl | BeCl2 | BCl3
B2Cl4 | CCl4 | NCl3
ClN3 | Cl2O
ClO2
Cl2O7 | ClF
ClF3
ClF5 | Ne
NaCl | MgCl2 | AlCl
AlCl3 | SiCl4 | P2Cl4
PCl3
PCl5 | S2Cl2
SCl2
SCl4 | Cl2 | Ar
KCl | CaCl
CaCl2 | ScCl3 | TiCl2
TiCl3
TiCl4 | VCl2
VCl3
VCl4
VCl5 | CrCl2
CrCl3
CrCl4 | MnCl2 | FeCl2
FeCl3 | CoCl2
CoCl3 | NiCl2 | CuCl
CuCl2 | ZnCl2 | GaCl2
GaCl3 | GeCl2
GeCl4 | AsCl3
AsCl5 | Se2Cl2
SeCl4 | BrCl | KrCl
RbCl | SrCl2 | YCl3 | ZrCl3
ZrCl4 | NbCl4
NbCl5 | MoCl2
MoCl3
MoCl4
MoCl5
MoCl6 | TcCl4 | RuCl3 | RhCl3 | PdCl2 | AgCl | CdCl2 | InCl
InCl2
InCl3 | SnCl2
SnCl4 | SbCl3
SbCl5 | Te3Cl2
TeCl4 | ICl
ICl3 | XeCl
XeCl2
CsCl | BaCl2 |  | HfCl4 | TaCl5 | WCl2
WCl3
WCl4
WCl5
WCl6 | Re3Cl9
ReCl4
ReCl5
ReCl6 | OsCl4 | IrCl2
IrCl3
IrCl4 | PtCl2
PtCl4 | AuCl
AuCl3 | Hg2Cl2,
HgCl2 | TlCl | PbCl2,
PbCl4 | BiCl3 | PoCl2,
PoCl4 | AtCl  | RnCl2
FrCl | RaCl2 |  | Rf  | Db  | Sg  | Bh  | Hs  | Mt  | Ds  | Rg  | Cn  | Nh  | Fl  | Mc  | Lv  | Ts  | Og
| ↓  |  |
LaCl3 | CeCl3 | PrCl3 | NdCl2,
NdCl3 | PmCl3 | SmCl2,
SmCl3 | EuCl2,
EuCl3 | GdCl3 | TbCl3 | DyCl2,
DyCl3 | HoCl3 | ErCl3 | TmCl2
TmCl3 | YbCl2
YbCl3 | LuCl3
AcCl3 | ThCl4 | PaCl5 | UCl3
UCl4
UCl5
UCl6 | NpCl4 | PuCl3 | AmCl2
AmCl3 | CmCl3 | BkCl3 | CfCl3 | EsCl3 | Fm  | Md  | No  | LrCl3

0.00

(0 votes)

Original source: https://en.wikipedia.org/wiki/Manganese(II) chloride. Read more

|

Retrieved from "https://handwiki.org/wiki/index.php?title=Chemistry:Manganese(II)_chloride&oldid=537559"
*[CID]: Compound ID
*[v]: View this template
*[t]: Discuss this template
*[e]: Edit this template