Iron (II) disulfide

Crystal structure
__ Fe 2+      __ __ S 2 2−
General
Surname	Iron (II) disulfide
other names	Pebbles Pyrite Marcasite
Ratio formula	FeS 2
Brief description	brass yellow to golden yellow crystals (pyrite) brass yellow to greenish crystals (marcasite)
External identifiers / databases
CAS number 1309-36-0 1317-66-4 12068-85-8 EC number 235-106-8 ECHA InfoCard 100.031.903 PubChem 123110 ChemSpider 102635 Wikidata Q1311146
properties
Molar mass	119.98 g · mol -1
Physical state	firmly
density	5.0 to 5.2 g cm −3 (pyrite) 4.87 g cm −3 (marcasite)
solubility	practically insoluble in water; insoluble in dilute acids; soluble in concentrated hydrochloric acid, HNO 3
safety instructions
GHS labeling of hazardous substances no GHS pictograms H and P phrases H: no H-phrases P: no P-phrases
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Iron (II) disulfide is the disulfide of divalent iron with the formula FeS ₂ .

Occurrence

Of course, iron (II) disulfide occurs in mineral form as pyrite or marcasite .

Extraction and presentation

Iron (II) disulfide can be produced by heating iron (II) sulfide with sulfur :

${\displaystyle \mathrm {FeS+S\longrightarrow FeS_{2}} }$

Iron (II) disulphide is also formed when hydrogen sulphide H ₂ S is passed over iron (III) oxide in red heat:

${\displaystyle \mathrm {Fe_{2}O_{3}+4\ H_{2}S\longrightarrow 2\ FeS_{2}+3\ H_{2}O+H_{2}} }$

properties

Pyrite crystals from Huansala, Huánuco Dep., Peru

Pure iron (II) disulfide forms gold or brass yellow crystals . In the cubic crystal form, iron (II) disulfide occurs naturally as pyrite . If pyrite is heated, this sulfur splits off and burns to sulfur dioxide SO ₂ and iron (III) oxide Fe ₂ O ₃ :

${\displaystyle \mathrm {4\ FeS_{2}+11\ O_{2}\longrightarrow 2\ Fe_{2}O_{3}+8\ SO_{2}} }$

Like iron (II) sulfide , it reacts with acids to form hydrogen sulfide (the disulfane (H ₂ S ₂ ) initially formed in this case is unstable under normal conditions and breaks down to H ₂ S and sulfur).

use

Iron (II) disulfide was previously used in large quantities for the production of sulfuric acid H ₂ SO ₄ . Nowadays it is used for the cathode of the lithium iron sulfide battery .

Individual evidence

1. ↑ Entry on pyrite. In: Römpp Online . Georg Thieme Verlag, accessed on June 19, 2014.
2. ↑ Entry on marcasite. In: Römpp Online . Georg Thieme Verlag, accessed on June 19, 2014.
3. ↑ ^{a b} D'Ans-Lax, pocket book for chemists and physicists , Volume 3 (1998); ISBN 3-540-60035-3
4. ↑ ^{a b c} Entry on iron disulfide in the GESTIS material database of the IFA , accessed on December 22, 2019 (JavaScript required)
5. ↑ Chemists Calendar; Synowietz, shepherd; Berlin, Heidelberg, 1984, pages 104-105
6. ^ 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.
7. ↑ Page no longer available , search in web archives: p. 7 (excerpt from: Inorganische Chemie, p. 287, Pearson, 2010)  ( Page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice.  
8. ↑ JCF van der Meer: Technical course starter batteries . Vieweg & Sohn, Braunschweig / Wiesbaden 1992, ISBN 978-3-322-86800-8 , p. 49 ( limited preview in Google Book search).