Iron (II) sulfide

Crystal structure
__ Fe 2+      __ S 2−
General
Surname	Iron (II) sulfide
other names	Sulphurous iron Iron monosulfide
Ratio formula	FeS
Brief description	dark gray or black metal-like pieces, plates or sticks
External identifiers / databases
CAS number 1317-37-9 EC number 215-268-6 ECHA InfoCard 100,013,881 PubChem 14828 ChemSpider 8466211 Wikidata Q407993
properties
Molar mass	87.91 g mol −1
Physical state	firmly
density	4.84 g cm −3
Melting point	1195 ° C
solubility	practically insoluble in water
safety instructions
GHS labeling of hazardous substances Caution H and P phrases H: 400 EUH: 031 P: 273
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Iron (II) sulfide (old name: sulfur iron ) is the sulfide of divalent iron with the formula FeS.

properties

Iron sulfide produced in the laboratory

Iron (II) sulfide is insoluble in water. It reacts with acids to form hydrogen sulfide :

${\displaystyle \mathrm {FeS+2\ HCl\longrightarrow FeCl_{2}+H_{2}S} }$

When heated to higher temperatures, a crystallographic transformation takes place in the solid state at 138 ° C and 325 ° C. Pure iron (II) sulfide forms light brown crystals of the nickel arsenide type. The technical goods are mostly colored dark to black by residual iron.

Manufacturing

Iron (II) sulfide can be produced both in the laboratory and technically by briefly heating a mixture of iron powder and sulfur powder in an exothermic reaction:

${\displaystyle \mathrm {Fe+S\longrightarrow FeS} }$

Occurrence

Iron (II) sulfide is found in nature as pyrrhotite , troilite and mackinawite .

The bacterial anaerobic corrosion can be recognized by the black coloration caused by iron (II) sulfide, which is the end product. This archaic metabolism of bacteria plays an important role in the iron-sulfur world , a scenario for the early evolution of life.

The green color of egg yolk comes from the - harmless - iron sulphide that is formed during long cooking (longer than 10 minutes).

use

Iron (II) sulfide was previously used for the synthesis of sulfuric acid . The iron (II) sulfide was roasted in the presence of air, producing the sulfur dioxide required for further synthesis . In the laboratory, iron (II) sulfide can be used to produce hydrogen sulfide . This can e.g. B. be carried out in the Kippschem apparatus .

See also

Iron (II) disulfide (FeS ₂ )

Individual evidence

1. ↑ ^{a b} Entry on iron sulfides. In: Römpp Online . Georg Thieme Verlag, accessed on July 15, 2014.
2. ↑ ^{a b c d} Entry on iron (II) sulphide in the GESTIS substance database of the IFA , accessed on July 23, 2016(JavaScript required) .
3. ^ D'Ans-Lax: Taschenbuch für Chemiker und Physiker , Volume 3 (1998), p. 458; ISBN 3-540-60035-3 .
4. ^ AF Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 102nd edition. Walter de Gruyter, Berlin 2007, ISBN 978-3-11-017770-1 , p. 1657.