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Potassium iodate

Potassium iodate

An unopened box of Potassium iodate
tablets, produced and distributed to
the population of the
Republic of Ireland following a
preparedness scandal relating to the
Sellafield nuclear power station
in the United Kingdom.

Other names iodic acid, potassium salt
Molecular formula KIO3
Molar mass 214.00 g/mol
Appearance white crystalline powder
CAS number [7758-05-6]
Density and phase 3.89 g/cm³, solid
Solubility in water 32g/100ml (100°C)
Melting point 560°C
partial decomposition
Boiling point  ?
EU classification not listed
NFPA 704
Related compounds
Other anions potassium iodide
potassium periodate
potassium bromate
potassium chlorate
Other cations sodium iodate
silver iodate
Except where noted otherwise, data are given for
materials in their standard state (at 25 °C, 100 kPa)
Infobox disclaimer and references

Potassium iodate (KIO3) is a chemical compound. It is sometimes used in radiation treatment, as it can replace radioactive iodine from the thyroid. See potassium iodide for more information on this use.

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

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, aluminum, organic compounds, carbon, hydrogen peroxide and sulfides.


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


    This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Potassium_iodate". A list of authors is available in Wikipedia.
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