View source for Potassium chlorate

{{chembox
| verifiedrevid = 399357775
|   Name = Potassium Chlorate
|   ImageFile = Potassium-chlorate-composition.png
|   ImageSize = 200px
|   ImageName = The structure of the ions in potassium chlorate
|   ImageFile1 = Potassium-chlorate-crystal-3D-vdW.png
|   ImageSize1 = 200px
|   ImageName1 = The crystal structure of potassium chlorate
|   ImageFile2 = Potassium chlorate-substance.jpg
|   ImageSize2 = 200px
|   ImageName2 = Potassium chlorate crystals <!--don't know why this didn't have a picture-->
|   OtherNames = Potassium chlorate(V), Potcrate
| Section1 = {{Chembox Identifiers
|   ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 18512
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = H35KS68EE7
| InChI = 1/ClHO3.K/c2-1(3)4;/h(H,2,3,4);/q;+1/p-1
| InChIKey = VKJKEPKFPUWCAS-REWHXWOFAC
| SMILES = [K+].[O-]Cl(=O)=O
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/ClHO3.K/c2-1(3)4;/h(H,2,3,4);/q;+1/p-1
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = VKJKEPKFPUWCAS-UHFFFAOYSA-M
| CASNo = 3811-04-9
|    CASNo_Ref = {{cascite|correct|CAS}}
|   PubChem = 6426889
|   EINECS = 223-289-7
|   RTECS = FO0350000
|   UNNumber = 1485
  }}
| Section2 = {{Chembox Properties
|   Formula = KClO<sub>3</sub>
|   MolarMass = 122.55 g/mol
|   Appearance = White crystals or powder
|   Density = 2.34 g/cm<sup>3</sup>
|   Solubility = 7.19 g/100 ml (20 °C) <br> 57 g/100 mL (100 °C)
|   SolubleOther = insoluble in [[acetone]], liquid [[ammonia]]
|   MeltingPt = 356 °C
|   BoilingPt = 400 °C ''decomp.''
|   RefractIndex = 1.40835
  }}
| Section3 = {{Chembox Structure
|   Coordination =
|   CrystalStruct = monoclinic
  }}
| Section7 = {{Chembox Hazards
|   ExternalMSDS = [http://www.ilo.org/public/english/protection/safework/cis/products/icsc/dtasht/_icsc05/icsc0548.htm ICSC 0548]
|   EUClass = Oxidant ('''O''')<br/>Harmful ('''Xn''')<br/>Dangerous for the environment ('''N''')
|   EUIndex = 017-004-00-3
|   RPhrases = {{R9}}, {{R22}}, {{R51/53}}
|   SPhrases = {{S2}}, {{S13}}, {{S16}}, {{S27}}, {{S61}}
|   NFPA-H = 2
|   NFPA-F = 0
|   NFPA-R = 3
|   NFPA-O = OX
|   FlashPt = 400 °C
|   LD50 = 1870 mg/kg
  }}
| Section8 = {{Chembox Related
|   OtherAnions = [[Potassium bromate]]<br/>[[Potassium iodate]]
|   OtherCations = [[Ammonium chlorate]]<br/>[[Sodium chlorate]]<br/>[[Barium chlorate]]
|   OtherCpds = [[Potassium chloride]]<br/>[[Potassium hypochlorite]]<br/>[[Potassium chlorite]]<br/>[[Potassium perchlorate]]
  }}
}}

'''Potassium chlorate''' is a compound containing [[potassium]], [[chlorine]] and [[oxygen]] atoms, with the molecular formula KClO<sub>3</sub>. In its pure form, it is a white crystalline substance. It is the most common [[chlorate]] in industrial use. It is used
* as an [[oxidizing agent]],
* to prepare [[oxygen]],
* as a [[disinfectant]],
* in safety [[match]]es,
* in [[explosives]] and [[fireworks]],
* in [[cultivation]], forcing the blossoming stage of the [[Longan]] tree, causing it to produce fruit in warmer climates.<ref>{{Cite journal
  | last1 = Manochai  | first1 = P.
  | last2 = Sruamsiri | first2 = P.
  | last3 = Wiriya-alongkorn | first3 = W.
  | last4 = Naphrom | first4 = D.
  | last5 = Hegele | first5 = M.
  | last6 = Bangerth | first6 = F.
  | title = Year around off season flower induction in longan (Dimocarpus longan, Lour.) trees by KClO3 applications: potentials and problems
  | journal = Scientia Horticulturae
  | volume = 104
  | issue = 4
  | pages = 379–390
  | location = Department of Horticulture, Maejo University, Chiang Mai, Thailand; Department of Horticulture, Chiang Mai University, Chiang Mai, Thailand; Institute of Special Crops and Crop Physiology, University of Hohenheim, 70593 Stuttgart, Germany
  | date = February 12, 2005
  | url = http://www.actahort.org/books/863/863_48.htm
  | accessdate = November 28, 2010}}</ref>

==Production==
The compound is industrially produced by passing chlorine into the hot water solution of [[potassium hydroxide]]. The [[electrolysis]] of [[Potassium chloride|KCl]] water solution is also used sometimes, then the chlorine formed at the [[anode]] reacts with KOH ''[[in situ]]''. As KClO<sub>3</sub> [[solubility]] in water decreases significantly when cooling, it can be simply isolated from the reaction mixture.

==Uses==
[[Image:KClO3-sugar1.gif|thumb|right|Potassium chlorate burning sugar]]
Potassium chlorate was one key ingredient in early [[firearms]] [[percussion cap]]s (primers). It continues in that application, where not supplanted by [[potassium perchlorate]].

Chlorate-based [[propellant]]s are more efficient than traditional [[gunpowder]] and are less susceptible to damage by water. However, they can be extremely unstable in the presence of [[sulfur]] or [[phosphorus]] and are much more expensive. Chlorate propellants must be used only in equipment designed for them; failure to follow this precaution is a common source of accidents.  Potassium chlorate, often in combination with [[silver fulminate]]{{Citation needed|date=February 2011}}, is used in trick [[firecracker|noise-makers]] known as "crackers", "snappers", "pop-its", or "bang-snaps", a popular type of novelty firework.

When mixed with a suitable fuel, it may form an [[explosive material]], a so-called [[Sprengel explosive]].  The [[hygroscopic]] and slightly weaker [[sodium chlorate]] is sometimes used as a safer and less expensive substitute for potassium chlorate.  In [[World War I]], mixes of potassium chlorate with [[plasticizer]]s (such as [[wax]]) were the most common type of [[plastic explosive]] used, often filling grenades and other munitions.  When used in explosives as an oxidizer, the explosive is [[explosive material#Low explosives|low order]] meaning it burns rapidly rather than explodes.  When mixed with a [[plasticizer]], it may become [[explosive material#High explosives|high order]], requiring a [[blasting cap]] (generally a commercial #8) to detonate properly. Potassium chlorate is rarely used in explosives now, as it is considered too sensitive for most uses.

Potassium chlorate is often used in high school and college laboratories to generate oxygen gas {{Citation needed|date=June 2009}}; it is a far cheaper source than a pressurized or cryogenic oxygen tank. Potassium chlorate will readily decompose if heated in contact with a [[catalyst]], typically [[manganese dioxide|manganese (IV) dioxide]] (MnO<sub>2</sub>). Thus, it may be simply placed in a test tube and heated over a burner. If the test tube is equipped with a one-holed stopper and hose, warm oxygen can be drawn off. The reaction is as follows:

: 2KClO<sub>3</sub>(s) + heat → 3O<sub>2</sub>(g) + 2KCl(s)

The safe performance of this reaction requires very pure reagents and careful temperature control. Molten potassium chlorate is an extremely powerful oxidizer and will spontaneously react with many common materials such as sugar. Explosions have resulted from liquid chlorates spattering into the latex or PVC tubes of oxygen generators, as well as from contact between chlorates and hydrocarbon sealing greases. Impurities in potassium chlorate itself can also cause problems. When working with a new batch of potassium chlorate, it is advisable to take a small sample (~ 1 gram) and heat it strongly on an open glass plate. Contamination may cause this small quantity to explode, indicating that the chlorate should be discarded.

Potassium chlorate is used in [[chemical oxygen generator]]s (also called chlorate candles or oxygen candles), employed as oxygen-supply systems of e.g. aircraft, space stations, and submarines, and has been responsible for at least one [[ValuJet Flight 592|plane crash]]. A fire on the space station [[Mir]] was also traced to this substance. The decomposition of potassium chlorate was also used to provide the oxygen supply for [[limelight]]s.

Potassium chlorate is used also as a [[pesticide]]. In Finland it was sold under trade name Fegabit.

Potassium chlorate can react with sulfuric acid to form a highly reactive solution of chloric acid and potassium sulfate:

: 2 KClO<sub>3</sub> + H<sub>2</sub>SO<sub>4</sub> → 2 HClO<sub>3</sub> + K<sub>2</sub>SO<sub>4</sub>

The solution so produced is sufficiently reactive that it will spontaneously ignite if combustible material (sugar, paper, etc) is present.

==Safety==
Potassium chlorate should be handled with care. It reacts vigorously, and in some cases spontaneously ignites or explodes, when mixed with many [[combustible]] materials. It will burn vigorously in combination with virtually any combustible material, even those which are considered to be only slightly flammable normally (including ordinary dust and lint). Mixtures of potassium chlorate and a fuel can be ignited by contact with sulfuric acid and this reagent should be kept away from potassium chlorate.
[[Sulfur]] should be avoided in pyrotechnic compositions containing potassium chlorate, as these mixtures are prone to spontaneous [[deflagration]]. Most sulfur contains trace quantities of sulfur-containing acids, and these can cause spontaneous ignition - "Flowers of sulfur" or "sublimed sulfur", despite the overall high purity, contains significant amounts of sulfur acids. Also, mixtures of potassium chlorate with any compound with ignition promoting properties (ex. [[antimony(III) sulfide]]) are very dangerous to prepare, as they are extremely shock sensitive.

==See also==
*[[Chloric acid]]

==References==
<references/>
*"Chlorate de potassium. Chlorate de sodium", ''Fiche toxicol. n° 217'', Paris:Institut national de recherche et de sécurité, 2000. 4pp.
*[http://www.freepatentsonline.com/5087334.html  Continuous process for the manufacture of potassium chlorate by coupling with a sodium chlorate production plant]

==External links==
*[http://cst-www.nrl.navy.mil/lattice/struk/g0_6.html Crystal structure of potassium chlorate (different projections)]
*[http://www.ilo.org/public/english/protection/safework/cis/products/icsc/dtasht/_icsc05/icsc0548.htm International Chemical Safety Card 0548]
*[http://www.youtube.com/watch?v=txkRCIPSsjM&feature=player_embedded#! Potassium chlorate and sugar]

{{Potassium compounds}}

[[Category:Potassium compounds]]
[[Category:Chlorates]]
[[Category:Pyrotechnic oxidizers]]

[[ca:Clorat de potassi]]
[[cs:Chlorečnan draselný]]
[[da:Kaliumklorat]]
[[de:Kaliumchlorat]]
[[es:Clorato de potasio]]
[[fr:Chlorate de potassium]]
[[hr:Kalijev klorat]]
[[lv:Kālija hlorāts]]
[[hu:Kálium-klorát]]
[[nl:Kaliumchloraat]]
[[ja:塩素酸カリウム]]
[[no:Kaliumklorat]]
[[pl:Chloran(V) potasu]]
[[pt:Clorato de potássio]]
[[ru:Хлорат калия]]
[[simple:Potassium chlorate]]
[[sk:Chlorečnan draselný]]
[[sr:Калијум хлорат]]
[[fi:Kaliumkloraatti]]
[[sv:Kaliumklorat]]
[[zh:氯酸钾]]