Copper Sulfide Precipitation

CuSO₄ + Na₂S → CuS↓ + Na₂SO₄

Aperçu

Copper sulfate reacts with sodium sulfide to form a black precipitate of copper(II) sulfide (Ksp = 1.3 × 10⁻³⁶). CuS is one of the most insoluble compounds known. The jet-black precipitate forms instantly and is used to identify Cu²⁺ ions in systematic qualitative analysis.

Participants

Rôle	Substance	Coefficient	État
Réactif	Copper(II) Sulfate CuSO₄	1	(aq)
Produit	Sodium Sulfate Na₂SO₄	1	(aq)

Exemple du quotidien

The black tarnish on copper pots exposed to sulfur-containing foods (eggs, garlic) is related to copper sulfide formation.

Importance industrielle

Sulfide precipitation is used in mining wastewater treatment to remove heavy metals. CuS (covellite) is also a naturally occurring copper ore mineral.

Propriétés

Type: Precipitation
Réversible: Non
Énergie: Exothermique
ΔH: -84,0 kJ/mol

Réactions associées

Aluminum Hydroxide Precipitation Barium Carbonate Precipitation Barium Sulfate Precipitation Cadmium Sulfide Precipitation (Yellow) Calcium Fluoride Precipitation (Fluorite) Calcium Phosphate Precipitation (Bone Mineral) Chromium(III) Hydroxide Precipitation Lead Carbonate Precipitation Lead Chloride Precipitation Iron(III) Hydroxide Precipitation

Frequently Asked Questions

What is the equation for Copper Sulfide Precipitation?

The balanced equation is: CuSO₄ + Na₂S → CuS↓ + Na₂SO₄.

What type of reaction is Copper Sulfide Precipitation?

Copper Sulfide Precipitation is a precipitation reaction.

Is Copper Sulfide Precipitation exothermic or endothermic?

Copper Sulfide Precipitation is exothermic (releases energy). The enthalpy change (ΔH) is -84.0 kJ/mol.