Mercury(II) iodide

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Template:Chembox E numberTemplate:Chembox SolubilityInWater
Mercury(II) iodide
Other names mercuric iodide
mercury biniodide
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Molar mass 454.40 g/mol
Appearance scarlet red powder
Density 6.36 g/cm³, solid
Melting point
Boiling point
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Mercury(II) iodide (HgI2) is a chemical compound with an appearance of red-orange crystals. Unlike mercury(II) chloride it is hardly soluble in water (<100 ppm).

Conditions/substances to avoid include: heat, light, bromides, chlorides, ammonia, alkalis, cyanides, copper salts, lead salts, iodoform and hydrogen peroxide.

Mercury(II) iodide displays thermochromism; when heated above 126 °C, it undergoes phase transition from the alpha crystalline form to a pale yellow beta form. As the sample cools, it gradually reacquires its original color. It is often used for thermochromism demonstrations. [1]

Mercury(II) iodide is used for preparation of Nessler's reagent, used for detection of presence of ammonia.

Mercury(II) iodide is a semiconductor material, used in some x-ray and gamma ray detection and imaging devices operating at room temperatures. [2]

In medicine, mercury(II) iodide was formerly used as a treatment for syphilis.

In veterinary medicine, mercury(II) iodide is used in blister ointments in exostoses, bursal enlargement, etc.

Mercury(II) iodide is one of the stated possibilities for the "red mercury".

See also



de:Quecksilber(II)-iodid it:Ioduro mercurico