Potassium iodate

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Potassium iodate
Names
IUPAC name
Potassium iodate
Other names
Iodic acid, potassium salt
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.028.938 Edit this at Wikidata
E number E917 (glazing agents, ...)
UNII
  • InChI=1S/HIO3.K/c2-1(3)4;/h(H,2,3,4);/q;+1/p-1 checkY
    Key: JLKDVMWYMMLWTI-UHFFFAOYSA-M checkY
  • InChI=1/HIO3.K/c2-1(3)4;/h(H,2,3,4);/q;+1/p-1
    Key: JLKDVMWYMMLWTI-REWHXWOFAL
  • [K+].[O-]I(=O)=O
Properties
KIO3
Molar mass 214.001 g/mol
Appearance white crystalline powder
Density 3.89 g/cm3
Melting point 560 °C decomp.
4.74 g/100 mL (0 °C)
32.3 g/100 mL (100 °C)
Solubility soluble in KI solution
insoluble in alcohol, liquid ammonia
Hazards
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 0: Will not burn. E.g. waterInstability 1: Normally stable, but can become unstable at elevated temperatures and pressures. E.g. calciumSpecial hazards (white): no code
2
0
1
Flash point Non-flammable
Related compounds
Other anions
 Potassium chlorate
Potassium bromate
Other cations
 Sodium iodate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Potassium iodate (KIO3) is a chemical compound.

Chemical properties

Potassium iodate is an oxidizing agent and as such it can cause fires if in contact with combustible materials or reducing agents. It can be prepared by reacting a potassium-containing base such as potassium hydroxide with iodic acid, for example:

HIO3 + KOH → KIO3 + H2O

It can also be prepared by adding iodine to a hot, concentrated solution of potassium hydroxide.

3 I2 + 6 KOH → KIO3 + 5 KI + 3 H2O

Conditions/substances to avoid include: heat, shock, friction, combustible materials, reducing materials, aluminium, organic compounds, carbon, hydrogen peroxide and sulfides.

Applications

Potassium iodate is sometimes used for iodination of table salt. Because iodide can be oxidized by molecular oxygen to iodine under wet conditions, US companies add thiosulfates or other antioxidants to the potassium iodide. In other countries, potassium iodate is used as source for iodine. It is also an ingredient in baby formula milk.

Like potassium bromate, potassium iodate is occasionally used as a maturing agent in baking.

Radiation protection

Potassium iodate may be used to protect against accumulation of radioactive iodine in the thyroid by saturating the body with a stable source of iodine prior to exposure.[1] Approved by the World Health Organization for radiation protection, potassium iodate (KIO3) is an alternative to potassium iodide (KI), which has poor shelf life in hot and humid climates.[2] The UK, Ireland, Singapore, United Arab Emirates, and US states Idaho and Utah are known[by whom?] to stock potassium iodate in tablet form.[citation needed] It is not approved by the U.S. Food and Drug Administration (FDA) for use as a thyroid blocker, and the FDA has taken action against US websites that promote this use.[3][4]

An unopened box of potassium iodate tablets, produced and distributed to the population of the Republic of Ireland in case of a terror attack on the Sellafield nuclear power station in the United Kingdom.
Recommended Dosage for Radiological Emergencies involving radioactive iodine[5]
Age KI in mg KIO3 in mg
Over 12 years old 130 170
3 - 12 years old 65 85
1 - 36 months old 32 42
< 1 month old 16 21

References

  1. ^ Astbury, John; Horsley, Stephen; Gent, Nick (1999), "Evaluation of a scheme for the pre-distribution of stable iodine (potassium iodate) to the civilian population residing within the immediate countermeasures zone of a nuclear submarine construction facility", Journal of Public Health, 21 (4): 2008–10, doi:10.1093/pubmed/21.4.412, PMID 11469363
  2. ^ Pahuja, D.N.; Rajan, M.G.; Borkar, A.V.; Samuel, A.M. (2008), "Potassium iodate and its comparison to potassium iodide as a blocker of 131I uptake by the thyroid in rats", Health physics, 65 (5): 545–9, doi:10.1097/00004032-199311000-00014, PMID 8225995 {{citation}}: Unknown parameter |month= ignored (help)
  3. ^ http://www.nukepills.com/potassium-iodate-vs-potassium-iodide.html
  4. ^ http://www.nukepills.com/docs/Potassium%20Iodate%20warning%20letter.pdf
  5. ^ Guidelines for Iodine Prophylaxis following Nuclear Accidents (PDF), Geneva: World Health Organization, 1999
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