Iron(II) Sulfide Precipitation
FeSO4 + Na2S → FeS↓ + Na2SO4
Overview
Iron(II) sulfate reacts with sodium sulfide to form a black precipitate of iron(II) sulfide (Ksp = 6 × 10⁻¹⁸). FeS reacts with dilute acids to produce hydrogen sulfide gas with its characteristic rotten egg smell. The mineral form is troilite, found in meteorites.
Participants
| Role | Substance | Coefficient | State |
|---|---|---|---|
| Product | Sodium Sulfate Na₂SO₄ | 1 | (aq) |
Everyday Example
The black spots in hard-boiled eggs at the yolk-white junction are iron sulfide, formed by reaction of iron in the yolk with sulfur from the egg white.
Industrial Importance
Iron sulfide is encountered in the petroleum industry as a corrosion product in sour gas wells and is the mineral pyrrhotite in geological formations.
Properties
- Type
- Precipitation
- Reversible
- No
- Energy
- Exothermic
- ΔH
- -75.0 kJ/mol
Related Reactions
Aluminum Hydroxide Precipitation
Barium Carbonate Precipitation
Barium Sulfate Precipitation
Cadmium Sulfide Precipitation (Yellow)
Calcium Carbonate Precipitation
Calcium Fluoride Precipitation (Fluorite)
Calcium Oxalate Precipitation (Kidney Stones)
Calcium Phosphate Precipitation (Bone Mineral)
Calcium Sulfate Precipitation (Gypsum)
Chromium(III) Hydroxide Precipitation
Frequently Asked Questions
What is the equation for Iron(II) Sulfide Precipitation?
The balanced equation is: FeSO₄ + Na₂S → FeS↓ + Na₂SO₄.
What type of reaction is Iron(II) Sulfide Precipitation?
Iron(II) Sulfide Precipitation is a precipitation reaction.
Is Iron(II) Sulfide Precipitation exothermic or endothermic?
Iron(II) Sulfide Precipitation is exothermic (releases energy). The enthalpy change (ΔH) is -75.0 kJ/mol.