Potassium periodate

Potassium periodate
Names
IUPAC name
Potassium periodate
Other names
potassium metaperiodate
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.029.269
EC Number
  • 232-196-0
UNII
UN number 3085
  • InChI=1S/HIO4.K/c2-1(3,4)5;/h(H,2,3,4,5);/q;+1/p-1 checkY
    Key: FJVZDOGVDJCCCR-UHFFFAOYSA-M checkY
  • InChI=1/HIO4.K/c2-1(3,4)5;/h(H,2,3,4,5);/q;+1/p-1
    Key: FJVZDOGVDJCCCR-REWHXWOFAS
  • [K+].[O-]I(=O)(=O)=O
Properties[1]
KIO4
Molar mass 229.999 g·mol−1
Appearance colorless tetrahedral crystals
Density 3.618 g/cm3
Melting point 582 °C (1,080 °F; 855 K)
Boiling point explodes
0.51 g/100g
3.71×10−4
Band gap 2.433 eV[2]
1.63[2]
Structure[2]
tetragonal
I41/a
4/m
a = 7.669 Å, b = 7.669 Å, c = 7.669 Å
α = 135.102°, β = 135.102°, γ = 65.371°
221.443 Å3
2
Thermochemistry[1]
175.7 J⋅mol−1·K-1
−467.2 kJ⋅mol−1
−361.4 kJ⋅mol−1
Hazards
GHS labelling:[3]
GHS03: OxidizingGHS08: Health hazardGHS05: CorrosiveGHS09: Environmental hazard
Danger
H271, H314, H372, H400
P210, P220, P221, P260, P264, P270, P273, P280, P283, P301+P330+P331, P303+P361+P353, P304+P340+P310, P305+P351+P338+P310, P306+P360, P314, P363, P370+P378, P371+P380+P375, P391, P405, P501
NFPA 704 (fire diamond)
[4]
NFPA 704 four-colored diamondHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilInstability 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazard OX: Oxidizer. E.g. potassium perchlorate
3
1
2
OX
Related compounds
Other anions
Other cations
 Sodium periodate
Related compounds
 Periodic acid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkYX markN ?)
Infobox references

Potassium periodate is an inorganic salt with the molecular formula KIO4. It is composed of a potassium cation and a periodate anion and may also be regarded as the potassium salt of periodic acid. Note that the pronunciation is per-iodate, not period-ate.

Unlike other common periodates, such as sodium periodate and periodic acid, it is only available in the meta-periodate form; the corresponding potassium ortho-periodate (K5IO6) has never been reported.

Preparation

Potassium periodate can be prepared by the oxidation of an aqueous solution of potassium iodate by chlorine and potassium hydroxide.[5]

KIO3 + Cl2 + 2 KOH → KIO4 + 2 KCl + H2O

It can also be generated by the electrochemical oxidation of potassium iodate, however the low solubility of KIO3 makes this approach of limited use.

Chemical properties

Potassium periodate decomposes at 582 °C (1,080 °F) to form potassium iodate and oxygen.

The low solubility of KIO4 makes it useful for the determination of potassium and cerium.[6]

On heating (especially with manganese(IV) oxide as catalyst), it decomposes to form potassium iodate, releasing oxygen gas.

References

  1. 1 2 Haynes, William M., ed. (2016). CRC Handbook of Chemistry and Physics (97th ed.). Boca Raton, Florida: CRC Press. pp. 4–80, 5–33, 5–178. ISBN 9781498754293.
  2. 1 2 3 "Potassium iodate(VII) - KIO4". legacy.materialsproject.org. Materials Project. doi:10.17188/1199594. Retrieved 14 May 2026.
  3. ↑ Sigma-Aldrich Co., Potassium periodate.
  4. ↑ "SDS - Potassium periodate". www.fishersci.com. ThermoFisher Scientific. 19 December 2025. Retrieved 14 May 2026.
  5. ↑ Schmeisser, M. Brauer, Georg (ed.). Handbook of preparative inorganic chemistry. Volume 1. Translated by Riley, Reed F. (2nd ed.). New York, N.Y.: Academic Press. p. 325. ISBN 978-0121266011.
  6. ↑ Venugopalan, M.; George, K. J. (1956). "Determination of cerium by potassium periodate". Die Naturwissenschaften. 43 (15): 348–349. doi:10.1007/BF00755157.
This page is issued from Wikipedia. The text is available under Creative Commons Attribution-Share Alike 4.0 unless otherwise noted. Additional terms may apply for the media files.