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 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 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.