Mercury(II) iodide

Mercury(II) iodide

Mercury(II) iodide (α form)

Mercury(II) iodide (β form)

β (left) and α (right) forms
Names
IUPAC name
Mercury(II) iodide
Other names
Mercury diiodide
Mercuric iodide
Red mercury (α form only)
Coccinite (α form only)
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
DrugBank
ECHA InfoCard 100.028.976 Edit this at Wikidata
EC Number
  • 231-873-8
277788
UNII
  • InChI=1S/Hg.2HI/h;2*1H/q+2;;/p-2 checkY
    Key: YFDLHELOZYVNJE-UHFFFAOYSA-L checkY
  • InChI=1/Hg.2HI/h;2*1H/q+2;;/p-2
    Key: YFDLHELOZYVNJE-NUQVWONBAE
  • I[Hg]I
Properties
HgI2
Molar mass 454.40 g/mol
Appearance orange-red powder
Odor odorless
Density 6.36 g/cm3
Melting point 259 °C (498 °F; 532 K)
Boiling point 350 °C (662 °F; 623 K)
6 mg/100 mL
2.9×10−29[1]
Solubility slightly soluble in alcohol, ether, acetone, chloroform, ethyl acetate, CS2, olive oil, castor oil

Soluble in excess KI(Potassium iodide) forming soluble complex K2[HgI4 ](Potassium tetraiodomercurate(II)) also known as Nessler's reagent

−128.6·10−6 cm3/mol
2.455
Structure
Tetrahedral
Pharmacology
D08AK30 (WHO)
Hazards
GHS labelling:
GHS06: ToxicGHS08: Health hazardGHS09: Environmental hazard
Danger
H300, H310, H330, H373, H410
P260, P262, P264, P270, P271, P273, P280, P284, P301+P310, P302+P350, P304+P340, P310, P314, P320, P321, P322, P330, P361, P363, P391, P403+P233, P405, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
3
0
0
Flash point Non-flammable
Related compounds
Other anions
 Mercury(II) fluoride
Mercury(II) chloride
Mercury(II) bromide
Other cations
 Zinc iodide
Cadmium iodide
Related compounds
 Mercury(I) iodide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

Mercury(II) iodide is a chemical compound with the molecular formula HgI2. It is typically produced synthetically but can also be found in nature as the extremely rare mineral coccinite. Unlike the related mercury(II) chloride it is hardly soluble in water (<100 ppm).

  1. ^ John Rumble (June 18, 2018). CRC Handbook of Chemistry and Physics (99 ed.). CRC Press. pp. 5–189. ISBN 978-1138561632.