Gourt Home::Gourt :: Iron(II) sulfide
| General | |
|---|---|
| Name | Iron sulfide, Iron(II) sulfide, Iron sulphide, Iron(II) sulphide |
| Chemical formula | FeS |
| Appearance | black solid |
The reaction can be explained by the following equation:
- S8 (s) + 8Fe (s) → 8FeS(s)
Forms
Iron (II) sulfide exists in several distinct forms, where the stoichiometry and properties differ slightly:
- Pyrrhotite - Fe1-xS - a very complicated form observed in mineralogical settings, and also as the waste product of the Desulfovibrio bacteria, pyrrhotite displays ferrimagnetism.
- Troilite - FeS - a very similar material to pyrrhotite, but does not possess ferromagnetic properties.
- Mackinawite - Fe1+xS - the least stable from of iron sulfide, Mackinawite has a layered structure similar to graphite.
Uses
Iron(II) sulfide itself doesn't have many real uses, but it is useful for demonstrating a certain number of chemical changes, especially exothermic reactions in laboratories.
The methods of chemical composition can be shown by the production of iron(II) sulfide from iron and sulfur:
- S8 (s) + 8Fe (s) → 8FeS(s)
As with most chemical reactions, a certain amount of energy is required to exceed the activation energy barrier. However, this reaction is exothermic and more energy is given out than taken in.
By reacting iron with sulfur into iron sulfide, teachers can show students that iron shows ferromagnetic properties only in elemental form as iron sulfide is not ferromagnetic.
By reacting iron sulfide with hydrochloric acid (HCl), the acidic properties of hydrochloric acid and the toxic, pungent fume of hydrogen sulfide can both be demonstrated:
- FeS(s) + 2HCl(aq) → FeCl2 (aq) + H2S(g)
By this reaction, teachers can also show changes of state caused by chemical changes.
See also
References
"Iron(II) sulfide"