Mercury(II) chloride

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Mercury(II) chloride
Mercury(II) chloride by NileRed.jpg
Freshly prepared mercury(II) chloride
IUPAC names
Mercury(II) chloride
Mercury dichloride
Other names
Corrosive sublimate
Mercuric chloride
Mercury bichloride
Molar mass 271.52 g/mol
Appearance White solid
Odor Odorless
Density 5.43 g/cm3
Melting point 276 °C (529 °F; 549 K)
Boiling point 304 °C (579 °F; 577 K)
3.6 g/100 ml (0 °C)
7.4 g/100 ml (20 °C)
48 g/100 ml (100 °C)
Solubility Soluble in glacial acetic acid, acetone, ethanol, ethyl acetate, formic acid, methanol, pentanol, THF
Slightly soluble in benzene, carbon disulfide, pyridine
Solubility in benzene 0.5 g/100 ml
Solubility in diethyl ether 4 g/100 ml
Solubility in ethanol 33 g/100 ml (25 °C)
Solubility in glycerol 8.3 g/100 ml
Acidity (pKa) 3.2 (0.2M solution)
144 J·mol−1·K−1
−230 kJ/mol
Safety data sheet Sigma-Aldrich
Flash point Non-flammable
Related compounds
Related compounds
Zinc chloride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Mercury(II) chloride or mercuric chloride is the chemical compound of mercury and chlorine with the formula HgCl2.



Mercury(II) chloride forms an amalgam with aluminium and prevents it from forming a protective oxide layer, which makes the metal susceptible to the action of water, alcohols. This property is exploited when synthesizing aluminium isopropoxide.


Mercuric chloride is a white solid, soluble in water and many organic solvents. It has the tendency to sublime.


Mercuric chloride is sold by chemical suppliers. It can also be sometimes found on eBay and Amazon.

The sale of mercury(II) chloride and most mercury compounds is restricted in many countries due to it's great toxicity. Its sale in EU is banned without a proper hazardous substance permit.


Mercury(II) chloride cannot be made by directly reacting mercury to hydrochloric acid or chlorine. Instead, mercury is converted to mercury(II) nitrate by reacting it with conc. nitric acid, which is either calcinated to mercury(II) oxide and then hydrochloric acid is added. While it's possible to obtain mercuric chloride by reacting the mercury(II) nitrate with hydrochloric acid, it's best to avoid this as the reaction produces the dangerously corrosive and toxic nitrosyl chloride, and it's possible some mercury(II) nitrate might be left unreacted.

Another route involves heating a mixture of mercury(II) sulfate and sodium chloride. HgCl2 is formed as vapors, and sublimes, condensing inside the reaction vessel. This route is very dangerous as the HgCl2 vapors are extremely toxic.




Mercury(II) chloride is extremely toxic and ingestion can lead to death. It can also be absorbed through the skin, much faster if it's dissolved in organic solvents.


Mercuric chloride should be stored in closed bottles, in a special cabinet.


Mercuric chloride should be converted to an insoluble form, such as mercury sulfide then taken to hazardous waste disposal centers.


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