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Potassium perchlorate

Potassium Perchlorate
Other names Perchlorated potassium
CAS number 7778-74-7
Molecular formula KClO4
Molar mass 138.55 g/mol
Appearance Colourless Crystalline Crystals or White Powder
Density 2.52 g/cm3, solid
Melting point

610 °C

Boiling point

400 °C

Solubility in water 1.5 g in 100 g[1]
EU classification Oxidant (O)
Harmful (Xn)
NFPA 704
Related Compounds
Other anions potassium chloride
potassium chlorate
potassium periodate
Other cations ammonium perchlorate
sodium perchlorate
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

Potassium perchlorate, a perchlorate salt with the chemical formula KClO4, is a strong oxidizer. It is a colorless, crystalline substance that melts at about 610 °C. It is one of the most common oxidizers used in fireworks, ammunition percussion caps, explosive primers, and is used variously in propellants, flash compositions, stars, and sparklers. It has been used as a solid rocket propellant, though in that application it has mostly been replaced by the higher performance ammonium perchlorate. KClO4 has the lowest solubility of all perchlorates (1.5 g in 100 g of water at 25 °C).[1]



As an oxidizer, KClO4 reacts with a wide variety of fuels. A common example is glucose, C6H12O6.

3 KClO4 + C6H12O6 → 6 H2O + 6 CO2 + 3 KCl

When mixed with cane sugar, it can be used as a low explosive, if the necessary confinement is provided. Otherwise the mixture will simply deflagrate with an intense purple flame indicative of potassium salts. Flash compositions used in firecrackers usually consist of fine aluminium powder mixed with potassium perchlorate.

Potassium perchlorate can be used safely in the presence of sulfur; however, potassium chlorate cannot. The common explanation for this is that the sulfur will, given time, produce minute quantities of sulfurous acid and sulfuric acid. These will, in turn, react with potassium chlorate to produce chloric acid, which is highly unstable and can lead to premature ignition of the composition. The corresponding acid of potassium perchlorate, perchloric acid, is stable enough as to prevent spontaneous ignition.


Potassium perchlorate is produced by double decomposition reaction with sodium perchlorate and potassium chloride. Sodium perchlorate is manufactured by anodic oxidation of sodium chloride.[2]

In medicine

Potassium perchlorate can be used as a potent antithyroid agent used to treat hyperthyroidism, usually in combination with one other medication.


  1. ^ a b Potassium Perchlorate MSDS. J.T. Baker (2007-02-16). Retrieved on 2007-12-10.
  2. ^ Perchlorate Production
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Potassium_perchlorate". A list of authors is available in Wikipedia.
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