Potassium iodate
Names
IUPAC name
Potassium iodate
Other names
Iodic acid, potassium salt
Identifiers
ChemSpider
DrugBank
ECHA InfoCard
100.028.938
EC Number
E number
E917 (glazing agents, ...)
RTECS number
UNII
InChI=1S/HIO3.K/c2-1(3)4;/h(H,2,3,4);/q;+1/p-1
Y Key: JLKDVMWYMMLWTI-UHFFFAOYSA-M
Y InChI=1/HIO3.K/c2-1(3)4;/h(H,2,3,4);/q;+1/p-1
Key: JLKDVMWYMMLWTI-REWHXWOFAL
Properties
KIO3
Molar mass
214.001 g/mol
Appearance
white crystalline powder
Odor
odorless
Density
3.89 g/cm3
Melting point
560 °C (1,040 °F; 833 K) (decomposes)
4.74 g/100 mL (0 °C) 9.16 g/100 mL (25 °C) 32.3 g/100 mL (100 °C)
Solubility
soluble in KI solution insoluble in alcohol , liquid ammonia , nitric acid
−63.1·10−6 cm3 /mol
Hazards
GHS labelling :
H272 , H302 , H318
P210 , P280 , P301+P312+P330 , P305+P351+P338+P310
NFPA 704 (fire diamond)
Flash point
Non-flammable
Related compounds
Potassium chlorate Potassium bromate
Sodium iodate
Related compounds
Potassium iodide Potassium periodate
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
Chemical compound
Potassium iodate (K I O3 ) is an ionic inorganic compound with the formula KIO3 . It is a white salt that is soluble in water.[ 1]
Preparation and properties
It can be prepared by reacting a potassium-containing base such as potassium hydroxide with iodic acid , for example:[ 1]
HIO3 + KOH → KIO3 + H2 O
It can also be prepared by adding iodine to a hot, concentrated solution of potassium hydroxide:[ 1]
3 I2 + 6 KOH → KIO3 + 5 KI + 3 H2 O
Or by fusing potassium iodide with potassium chlorate , bromate or perchlorate , the melt is extracted with water and potassium iodate is isolated from the solution by crystallization:[ 2]
KI + KClO3 → KIO3 + KCl
The analogous reaction with potassium hypochlorite is also possible:[ 3]
KI + 3KOCl → 3KCl + KIO3
Conditions/substances to avoid include: heat , shock , friction ,[ 4] combustible materials,[ 1] reducing materials, aluminium ,[ 4] organic compounds ,[ 1] carbon , hydrogen peroxide and sulfides .[ 4]
Applications
Potassium iodate is sometimes used for iodination of table salt to prevent iodine deficiency . In the US, iodized salt contains antioxidants , because atmospheric oxygen can oxidize wet iodide to iodine; other countries simply use potassium iodate instead.[ 5] Salt mixed with ferrous fumarate and potassium iodate, "double fortified salt", are used to address both iron and iodine deficiencies.[ 6] Potassium iodate is also used to provide iodine in some baby formula .[ 7]
Like potassium bromate , potassium iodate is occasionally used as a maturing agent in baking.[ 8]
Radiation protection
An unopened box of potassium iodate tablets distributed in the early 2000s to Irish households in case of a terror attack on British nuclear facilities.
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.[ 9] 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 .[ 10] The UK , Singapore , United Arab Emirates , and the U.S. states Idaho and Utah all maintain potassium iodate tablets towards this end.[citation needed ] Following the September 11 attacks , the government of Ireland issued potassium iodate tablets to all households for a similar purpose.[ 11]
Recommended Dosage for Radiological Emergencies involving radioactive iodine[ 12]
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
Potassium iodate 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.[ 13] [ 14]
Safety
Potassium iodate is an oxidizing agent and as such it can form explosive mixtures when combined with organic compounds.[ 1]
References
^ a b c d e f Lyday, Phyllis A.; Kaiho Tatsuo (26 November 2015). "Iodine and Iodine Compounds". In Ley, Claudia (ed.). Ullmann's Encyclopedia of Industrial Chemistry (7th ed.). Weinheim: Wiley-VCH. p. 9. doi :10.1002/14356007.a14_381.pub2 . ISBN 9783527306732 .
^ Pradyot Patnaik. Handbook of Inorganic Chemicals . McGraw-Hill, 2002, ISBN 0-07-049439-8
^ Andrews, Launcelot W. (July 1903). "Titrations with potassium iodide" . Journal of the American Chemical Society . 25 (7). Easton, Pennsylvania : US Postal Service : 756. doi :10.1021/ja02009a012 – via HathiTrust .
^ a b c Regulatory Affairs (23 March 2023). "Safety Data Sheet" (Potassium iodate MSDS) (5 ed.). Fair Lawn, NJ : Thermo Fisher Scientific . Archived from the original on 22 September 2023. Retrieved 22 September 2023 .
^ Arroyave, Guillermo; Pineda, Oscar; Scrimshaw, Nevin S. (1956) [May 1955]. "The stability of potassium iodate in crude table salt" . Bulletin of the World Health Organization . 14 (1): 183–185. PMC 2538103 . PMID 13329845 .
^ Diosady, Levente L.; Mannar, M.G. Venkatesh; Krishnaswamy, Kiruba (2019). "Improving the lives of millions through new double fortification of salt technology" . Maternal & Child Nutrition . 15 (Suppl 3): e12773. doi :10.1111/mcn.12773 . PMC 6594086 . PMID 31148400 .
^ James, Maia (2023-04-04). "Best Baby Formula Guide" . Gimme the Good Stuff . Retrieved 2023-09-22 .
^ Carson, Lin (ed.). "Potassium iodate" . BAKERpedia . Portland, OR . Retrieved 22 September 2023 .
^ 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 , archived from the original on 2008-09-05
^ Pahuja, D.N.; Rajan, M.G.; Borkar, A.V.; Samuel, A.M. (Nov 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
^ "Decision to Discontinue the Future Distribution of Iodine Tablets" . Archived from the original on 2013-10-18. Retrieved 2013-05-22 .
^ Guidelines for Iodine Prophylaxis following Nuclear Accidents (PDF) , Geneva: World Health Organization , 1999
^ "Potassium iodide vs potassium iodate. Which one works?" .
^ W. Charles Becoat (29 May 2003). "Potassium Iodate Warning Letter" (PDF) . Food and Drug Administration.
H, (pseudo)halogens chalcogens pnictogens B, C group transition metals organic