Manganese (II) sulfide

Crystal structure
__ Mn 2+      __ S 2−
General
Surname	Manganese (II) sulfide
other names	Manganese sulfide Manganese monosulfide
Ratio formula	MnS
Brief description	green or red powder
External identifiers / databases
CAS number 18820-29-6 EC number 242-599-3 ECHA InfoCard 100,038,711 PubChem 87809 Wikidata Q419893
properties
Molar mass	87.00 g mol −1
Physical state	firmly
density	3.99 g cm −3 (20 ° C)
Melting point	1610 ° C
solubility	practically insoluble in water (4.7 mg l −1 at 18 ° C)
safety instructions
GHS labeling of hazardous substances Caution H and P phrases H: 315-319-317-411 P: 261-305 + 351 + 338
MAK	0.55 mg m −3 (based on Mn)
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Manganese (II) sulfide is a chemical compound between manganese and sulfur , which occurs in nature as the mineral alabandin or rambergite . Chemically it belongs to the class of salts , more precisely the metal sulfides .

Occurrence

Manganese sulfide occurs not only as a mineral but also as an inclusion in alloyed steels , whereby the sulfur present in the pig iron combines with the manganese. The manganese sulfide improves the so-called machinability . Steels containing manganese sulfide are therefore easier to drill, mill or turn . (See Machinability # Non-Ferrous Metals .)

Extraction and presentation

α-Manganese (II) sulfide can be obtained by reacting a manganese (II) salt solution (e.g. manganese (II) chloride ) with a hot ammonium sulfide solution.

${\displaystyle \mathrm {(NH_{4})_{2}S+\ MnCl_{2}\longrightarrow 2\ NH_{4}Cl+\ MnS} }$

The β-modification can be produced by reacting a cold solution of manganese (II) acetate tetrahydrate with hydrogen sulfide .

The γ-modification can be obtained by reacting manganese (II) hydroxide with hydrogen sulfide at 100 ° C.

properties

Manganese (II) sulfide

Manganese (II) sulfide occurs in three modifications. The green α-manganese (II) sulfide has a crystal structure of the sodium chloride type (a = 522.4 pm). The red β-manganese (II) sulfide has a crystal structure of the zinc blende type (a = 560 pm). The γ-manganese (II) sulfide, which is also red, has a crystal structure of the wurtzite type (a = 397.6 pm, c = 643.2 pm). Since the two red modifications are metastable, they transform into the stable green modification in the dry state from 200 ° C at a noticeable rate, faster at 300 ° C. The red modifications also differ from the α modification in their magnetic behavior.

See also

• Manganese (II) sulfate , MnSO ₄

Individual evidence

1. ↑ ^{a b c d e} Georg Brauer (Ed.) U. a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume III, Ferdinand Enke, Stuttgart 1981, ISBN 3-432-87823-0 , p. 1587ff.
2. ↑ ^{a b c} data sheet manganese (II) sulfide from AlfaAesar, accessed on January 29, 2010 ( PDF )(JavaScript required) .
3. ↑ Entry on manganese (II) sulfide at Webelements.
4. ↑ Entry on manganese sulfide in the GESTIS substance database of the IFA , accessed on January 10, 2017(JavaScript required) .
5. ↑ Data sheet Manganese (II) sulfide from Sigma-Aldrich , accessed on February 1, 2017 ( PDF ).
6. ^ Hans Kurt Tönshoff, Berend Denkena: Spanen: Basis . 2nd Edition. Springer-Verlag, Berlin / Heidelberg 2004, ISBN 978-3-662-09963-6 , pp. 132 ( limited preview in Google Book search).
7. ↑ Fritz Klocke, Wilfried König: Production Process Volume 1: Turning, Milling, Drilling. 8th edition, Springer, 2008, p. 278.