Calcium iodate

Calcium iodates are inorganic compound composed of calcium and iodate anion. Two forms are known, anhydrous Ca(IO3)2 and the hexahydrate Ca(IO3)2(H2O). Both are colourless salts that occur naturally as the minerals called lautarite and bruggenite, respectively. A third mineral form of calcium iodate is dietzeite, a salt containing chromate with the formula Ca2(IO3)2CrO4.[1]

Calcium iodate
Calcium iodate.png
IUPAC name
Calcium diiodate
Other names
  • 7789-80-2 (anhydrous) checkY
  • 10031-33-1 (hexahydrate) ☒N
3D model (JSmol)
ECHA InfoCard 100.029.265 Edit this at Wikidata
EC Number
  • 232-191-3
E number E916 (glazing agents, ...)
  • InChI=1S/Ca.2HIO3/c;2*2-1(3)4/h;2*(H,2,3,4)/q+2;;/p-2 checkY
  • InChI=1/Ca.2HIO3/c;2*2-1(3)4/h;2*(H,2,3,4)/q+2;;/p-2
  • [Ca+2].[O-]I(=O)=O.[O-]I(=O)=O
Molar mass 389.88 g/mol (anhydrous)
407.90 g/mol (monohydrate)
Appearance white solid
Density 4.519 g/cm3 (monohydrate)
Melting point 540 °C (1,004 °F; 813 K) (monohydrate)
Boiling point decomposes
0.09 g/100 mL (0 °C)
0.24 g/100 mL (20 °C)
0.67 g/100 mL (90 °C)
Solubility soluble in nitric acid
insoluble in alcohol
-101.4·10−6 cm3/mol
monoclinic (anhydrous)
cubic (monohydrate)
orthorhombic (hexahydrate)
Flash point non-flammable
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Production and reactionsEdit

Lautarite, described as the most important mineral source of iodine, is mined in the Atacama Desert.[1] Processing of the ore entails reduction of its aqueous extracts with sodium bisulfite to give sodium iodide. Via a comproportionation reaction, the sodium iodide is combined with the iodate salt to produce elemental iodine.[1] Calcium iodate can be produced by the anodic oxidation of calcium iodide or by passing chlorine into a hot solution of lime in which iodine has been dissolved.


Calcium iodate can also be used as an iodine supplement in chicken feed.[1]

Calcium iodate is used in the manufacture of disinfectants, antiseptics, and deodorants.[2][3]


  1. ^ a b c d Lyday, Phyllis A.; Tatsuo Kaiho"Iodine and Iodine Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, 2015, Wiley-VCH, Weinheim, doi:10.1002/14356007.a14_381.pub2 Vol. A14 pp. 382–390.
  2. ^ "Calcium Iodate".
  3. ^ Calcium iodate[dead link] from the Online Medical Dictionary