Potassium perchlorate

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Potassium Perchlorate Image:Kclo4.PNG

General
Other names	perchloric acid, potassium salt
Molecular formula	KClO₄
Molar mass	138.55 g/mol
Appearance	Colourless Crystalline Crystals or White Powder
CAS number	[7778-74-7]
Properties
Density and phase	2.52 g/cm³, solid
Solubility in water	1.5g in 100g H₂O
Melting point	610 °C
Boiling point	400°C
Structure
Coordination geometry	?
Crystal structure	?
Hazards
MSDS	[MSDS]
EU classification	Oxidant (O) Harmful (Xn)
NFPA 704	Image:NFPA 704.svg 0 2 2 OX
R-phrases
S-phrases
Flash point
Related compounds
Other anions
Other cations
Related compounds	Potassium chloride Potassium chlorate
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Potassium perchlorate, chemical formula K Cl O₄, 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, used variously in propellants, flash compositions, stars, and sparklers. It has been used as a solid rocket propellant, though it has mostly been replaced by the higher performance ammonium perchlorate.

It has a molar mass of 138.55 g/mol.

[edit] Reactions

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

And when mixed with cane sugar, can be used as a low explosive, if the necessary confinement is provided. Otherwise the mixture will simply deflagrate. 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 can't. The common explanation for this is that the sulfur will, given time, produce minute quantities of sulfurous 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.