Iron(II) sulfide

Iron(II) sulfide
Sample of iron(II) sulfide
Names
Other names
Iron sulfide, ferrous sulfide, black iron sulfide, protosulphuret of iron
Identifiers
CAS Number
  • 1317-37-9 checkY
3D model (JSmol)
  • Interactive image
ChemSpider
  • 8466211 checkY
ECHA InfoCard 100.013.881 Edit this at Wikidata
PubChem CID
  • 10290742
UNII
  • TH5J4TUX6S checkY
CompTox Dashboard (EPA)
  • DTXSID5061665 Edit this at Wikidata
InChI
  • InChI=1S/Fe.S/q+2;-2 checkY
    Key: GNVXPFBEZCSHQZ-UHFFFAOYSA-N checkY
  • InChI=1/Fe.S/q+2;-2
    Key: GNVXPFBEZCSHQZ-UHFFFAOYAC
  • [Fe+2].[S-2]
Properties
Chemical formula
FeS
Molar mass 87.910 g/mol
Appearance Grey, sometimes in lumps or powder
Density 4.84 g/cm3
Melting point 1,194 °C (2,181 °F; 1,467 K)
Solubility in water
negligible (insoluble)
Solubility reacts in acid
Magnetic susceptibility (χ)
+1074·10−6 cm3/mol
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
Source of hydrogen sulfide, can be pyrophoric
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 1: Exposure would cause irritation but only minor residual injury. E.g. turpentineFlammability 2: Must be moderately heated or exposed to relatively high ambient temperature before ignition can occur. Flash point between 38 and 93 °C (100 and 200 °F). E.g. diesel fuelInstability 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazards (white): no code
1
2
2
Autoignition
temperature
variable
Related compounds
Other anions
Iron(II) oxide
Iron(II) selenide
Iron(II) telluride
Other cations
Manganese(II) sulfide
Cobalt(II) sulfide
Related Iron sulfides
Iron(III) sulfide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references
Chemical compound

Iron(II) sulfide or ferrous sulfide (Br.E. sulphide) is one of a family of chemical compounds and minerals with the approximate formula FeS. Iron sulfides are often iron-deficient non-stoichiometric. All are black, water-insoluble solids.

Preparation and structure

FeS can be obtained by the heating of iron and sulfur:[1]

Fe + S → FeS

FeS adopts the nickel arsenide structure, featuring octahedral Fe centers and trigonal prismatic sulfide sites.

Reactions

Iron sulfide reacts with hydrochloric acid, releasing hydrogen sulfide:[2]

FeS + 2 HCl → FeCl2 + H2S
FeS + H2SO4 → FeSO4 + H2S

In moist air, iron sulfides oxidize to hydrated ferrous sulfate.

Biology and biogeochemistry

An overcooked hard-boiled egg, showing the distinctive green coating on the yolk caused by the presence of iron(II) sulfide

Iron sulfides occur widely in nature in the form of iron–sulfur proteins.

As organic matter decays under low-oxygen (or hypoxic) conditions such as in swamps or dead zones of lakes and oceans, sulfate-reducing bacteria reduce various sulfates present in the water, producing hydrogen sulfide. Some of the hydrogen sulfide will react with metal ions in the water or solid to produce iron or metal sulfides, which are not water-soluble. These metal sulfides, such as iron(II) sulfide, are often black or brown, leading to the color of sludge.

Pyrrhotite is a waste product of the Desulfovibrio bacteria, a sulfate reducing bacteria.

When eggs are cooked for a long time, the yolk's surface may turn green. This color change is due to iron(II) sulfide, which forms as iron from the yolk reacts with hydrogen sulfide released from the egg white by the heat.[3] This reaction occurs more rapidly in older eggs as the whites are more alkaline.[4]

The presence of ferrous sulfide as a visible black precipitate in the growth medium peptone iron agar can be used to distinguish between microorganisms that produce the cysteine metabolizing enzyme cysteine desulfhydrase and those that do not. Peptone iron agar contains the amino acid cysteine and a chemical indicator, ferric citrate. The degradation of cysteine releases hydrogen sulfide gas that reacts with the ferric citrate to produce ferrous sulfide.

See also

References

  1. ^ H. Lux "Iron (II) Sulfide" in Handbook of Preparative Inorganic Chemistry, 2nd Ed. Edited by G. Brauer, Academic Press, 1963, NY. Vol. 1. p. 1502.
  2. ^ Hydrogen Sulfide Generator
  3. ^ Belle Lowe (1937), "The formation of ferrous sulfide in cooked eggs", Experimental cookery from the chemical and physical standpoint, John Wiley & Sons
  4. ^ Harold McGee (2004), McGee on Food and Cooking, Hodder and Stoughton
  • v
  • t
  • e
Fe(-II)
  • H2Fe(CO)4
  • Na2Fe(CO)4
Fe(0)
  • Fe(CO)5
  • Fe2(CO)9
  • Fe3(CO)12
  • Fe(CO)3CH3COC2H2C6H6
Fe(I)
  • FeH
Organoiron(I) compounds
  • (C5H5FeCO)2(CO)2
  • Fe(0,II)
    • Fe3C
    Fe(II)
    • FeH2
    • Mg2FeH6
    • FeF2
    • FeCl2
    • Fe(ClO4)2
    • FeBr2
    • FeI2
    • FeO
    • Fe(OH)2
    • FeS
    • FeSO4
    • (NH4)2Fe(SO4)2·6H2O
    • FeSe
    • FeSeO4
    • Fe(NO3)2
    • Fe3(PO4)2
    • FeSi2
    • Fe(BF4)2
    • FeCr2O4
    • FeMoO4
    • FeTiO3
    • FeCO3
    • FeC2O4
    • Fe(C2H3O2)2
    • Fe(C3H5O3)2
    • FeC6H6O7
    • FeC12H22O14
    • FeI2(CO)4
    Organoiron(II) compounds
    • Fe(C5H5)2
    • Fe(C5H5)(CO)2I
    • Fe(C5H4P(C6H5)2)2
    • C4H4Fe(CO)3
    • C4H6Fe(CO)3
    Fe(0,III)Fe(II,III)
    • Fe3O4
    • Fe3S4
    Fe(III)
    • FeI3
    • FeBr3
    • FeCl3
    • FeF3
    • FeP
    • Fe(NO3)3
    • Fe(acac)3
    • FeOCl
    • [(C2H5)4N][O(FeCl3)2]
    • FeO(OH)
    • FePO4
    • Fe4(P2O7)3
    • Fe2(CrO4)3
    • Fe2(C2O4)3
    • Fe2O3
    • Fe2(SeO3)3
    • Fe2S3
    • Fe2(SO4)3
    • Fe(N3)3
    • NH4Fe(SO4)2·12H2O
    Organoiron(III) compounds
    • Fe(C5H5)2BF4
    • C6H8O7⋅xFe3+⋅yNH3
    • C
      54
      H
      105
      FeO
      6
    Fe(IV)
    • FeF4
    Fe(VI)
    • K2FeO4
    • BaFeO4
    Purported
    • v
    • t
    • e
    Sulfides (S2−)
    H2S He
    Li2S BeS B2S3
    +BO3
    CS2
    COS
    (NH4)SH O F Ne
    Na2S MgS Al2S3 SiS
    SiS2
    -Si
    PxSy
    -P
    -S2−
    2
    Cl Ar
    K2S CaS ScS
    Sc2S3
    TiS
    TiS2
    Ti2S3
    TiS3
    VS
    VS2
    V2S3
    CrS
    Cr2S3
    MnS
    MnS2
    FeS
    Fe3S4
    CoS NiS Cu2S
    CuS
    ZnS GaS
    Ga2S3
    GeS
    GeS2
    -Ge
    As2S3
    As4S3
    -As
    SeS2
    +Se
    Br Kr
    Rb2S SrS Y2S3 ZrS2 NbS2 MoS2
    MoS3
    Tc Ru Rh2S3 PdS Ag2S CdS In2S3 SnS
    SnS2
    -Sn
    Sb2S3
    Sb2S5
    -Sb
    TeS2 I Xe
    Cs2S BaS * LuS
    Lu2S3
    HfS2 TaS2 WS2
    WS3
    ReS2
    Re2S7
    OsS
    4
    Ir2S3
    IrS2
    PtS
    PtS2
    Au2S
    Au2S3
    HgS Tl2S PbS
    PbS2
    Bi2S3 PoS At Rn
    Fr Ra ** Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Nh Fl Mc Lv Ts Og
     
    * LaS
    La2S3
    CeS
    Ce2S3
    PrS
    Pr2S3
    NdS
    Nd2S3
    Pm2S3 SmS
    Sm2S3
    EuS
    Eu2S3
    GdS
    Gd2S3
    TbS
    Tb2S3
    DyS
    Dy2S3
    HoS
    Ho2S3
    ErS
    Er2S3
    TmS
    Tm2S3
    YbS
    Yb2S3
    ** Ac2S3 ThS2 Pa US
    US2
    Np Pu Am Cm Bk Cf Es Fm Md No