Mercury(II) Sulfide Precipitation (Vermilion)
HgCl2 + Na2S → HgS↓ + 2NaCl
Tổng quan
Mercury(II) chloride reacts with sodium sulfide to form a black precipitate of mercury(II) sulfide (Ksp = 2 × 10⁻⁵²), the most insoluble compound commonly encountered. The black form (metacinnabar) slowly converts to the red form (cinnabar/vermilion) upon heating. HgS is so insoluble it is considered environmentally immobile.
Người tham gia
| Vai trò | Chất | Hệ số | Trạng thái |
|---|---|---|---|
| Sản phẩm | Sodium Chloride NaCl | 2 | (aq) |
Ví dụ thực tế
Vermilion pigment, prized since antiquity for its brilliant red color in Chinese lacquerware and Renaissance paintings, is red mercury sulfide.
Tầm quan trọng công nghiệp
Mercury sulfide as cinnabar is the primary mercury ore. HgS immobilization is used in mercury waste stabilization because of its extreme insolubility.
Tính chất
- Loại
- Precipitation
- Thuận nghịch
- Không
- Năng lượng
- Tỏa nhiệt
- ΔH
- -83,0 kJ/mol
Phản ứng liên quan
Aluminum Hydroxide Precipitation
Barium Sulfate Precipitation
Cadmium Sulfide Precipitation (Yellow)
Calcium Phosphate Precipitation (Bone Mineral)
Chromium(III) Hydroxide Precipitation
Lead Carbonate Precipitation
Magnesium Hydroxide Precipitation
Copper Sulfide Precipitation
Cobalt(II) Hydroxide Precipitation
Iron(III) Hydroxide Precipitation
Frequently Asked Questions
What is the equation for Mercury(II) Sulfide Precipitation (Vermilion)?
The balanced equation is: HgCl₂ + Na₂S → HgS↓ + 2NaCl.
What type of reaction is Mercury(II) Sulfide Precipitation (Vermilion)?
Mercury(II) Sulfide Precipitation (Vermilion) is a precipitation reaction.
Is Mercury(II) Sulfide Precipitation (Vermilion) exothermic or endothermic?
Mercury(II) Sulfide Precipitation (Vermilion) is exothermic (releases energy). The enthalpy change (ΔH) is -83.0 kJ/mol.