Wikipedia:WikiProject Chemicals/Chembox validation/VerifiedDataSandbox and Potassium permanganate: Difference between pages

| verifiedrevid = 464362108

| Name = Potassium permanganate

| ImageFile1 = KMnO4.svg

| ImageSize1 = 144px

| ImageFile2 = Potassium-permanganate-2004-unit-cell-3D-balls.png

| ImageFile3 = Potassium-permanganate-sample.jpg

| ImageSize3 = 220px

| IUPACName = Potassium manganate(VII)

| SystematicName = Potassium permanganate

| OtherNames = Chameleon mineral<br />Condy's crystals<br />Permanganate of potash <br />Hypermangan<br />Purple potion powder

| Section1 = {{Chembox Identifiers

|CASNo = 7722-64-7

|CASNo_Ref = {{cascite|correct|CAS}}

|PubChem = 516875

|ChemSpiderID = 22810

|SMILES = [K+].[O-][Mn](=O)(=O)=O

|StdInChI_Ref = {{stdinchicite|correct|chemspider}}

|StdInChI=1S/K.Mn.4O/q+1;;;;;-1

|StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}

|StdInChIKey = VZJVWSHVAAUDKD-UHFFFAOYSA-N

|RTECS = SD6475000

|KEGG_Ref = {{keggcite|correct|kegg}}

|KEGG = D02053

|UNNumber = 1490

|EINECS = 231-760-3

|DrugBank = DB13831

|UNII = 00OT1QX5U4

|ChEMBL = 3833305

| Section2 = {{Chembox Properties

|Formula = KMnO₄

|MolarMass = 158.034 g/mol

|Appearance = Purplish-bronze-gray needles<br /> purple in solution<ref name="Burriel_1985">{{cite book | vauthors = Burriel F, Lucena F, Arribas S, Hernández J | date = 1985 | title = Química Analítica Cualitativa | trans-title = Qualitative Analytical Chemistry | language = Spanish | page = 688 | publisher = Ediciones Paraninfo, S.A. | isbn = 84-9732-140-5}}</ref>

|Odor = odorless

|Density = 2.7 g/cm³<ref name=crc>{{cite book | veditors = Haynes WM | year = 2011 | title = CRC Handbook of Chemistry and Physics | edition = 92nd | publisher = [[CRC Press]] | isbn = 978-1439855119| title-link = CRC Handbook of Chemistry and Physics }}</ref>{{rp|4.83}}

|MeltingPtC = 240

|MeltingPt_notes = (decomposes)

|Solubility = 76 g/L (25 °C)<ref name=crc/><br /> 250 g/L (65 °C)

|SolubleOther = soluble in organic solvents; decomposes in [[Alcohol (chemistry)|alcohol]]

|RefractIndex = 1.59

|MagSus = +20.0·10⁻⁶ cm³/mol<ref name=crc/>{{rp|4.134}}

}}

| Section3 = {{Chembox Structure

|Structure_ref =<ref>{{cite journal | vauthors = Hocart R, Mathieu-Sicaud A | title = A stabilization factor in the polymorphism of ammonium nitrate | date = 1945 | journal = Comptes Rendus Hebdomadaires des Séances de l'Académie des Sciences | trans-journal = Weekly Reports of the Sessions of the Academy of Sciences | language = French | volume = 221 | pages = 261–263 }}</ref>

|CrystalStruct = [[Orthorhombic]], [[Pearson symbol|oP24]]

|SpaceGroup = Pnma, No. 62

|LattConst_a = 0.909 nm

|LattConst_b = 0.572 nm

|LattConst_c = 0.741 nm

|UnitCellFormulas = 4

}}

| Section4 = {{Chembox Thermochemistry

|DeltaHf = −813.4 kJ/mol

|Entropy = 171.7 J&thinsp;K⁻¹&thinsp;mol⁻¹

|HeatCapacity = 119.2 J/mol K

|DeltaGf = -713.8 kJ/mol

}}

| Section5 = {{Chembox Pharmacology

|ATCCode_prefix = D08

|ATCCode_suffix = AX06

|ATC_Supplemental = {{ATC|V03|AB18}}

}}

| Section6 = {{Chembox Hazards

|GHSPictograms = {{GHS03}} {{GHS07}} {{GHS09}}

|NFPA-H = 2

|NFPA-F = 0

|NFPA-R = 2

|NFPA-S = OX

|LD50 = 1090 mg/kg (oral, rat)<ref>{{cite web|url=https://chem.nlm.nih.gov/chemidplus/rn/7722-64-7|id = ChemIDplus – CAS: 7722-64-7 InChi: VZJVWSHVAAUDKD-UHFFFAOYSA-N | title = Potassium permanganate [USP:JAN] – Similar structures search, synonyms, formulas, resource links, and other chemical information. | vauthors = Chambers M | work = ChemIDplus: A Toxnet database | publisher = U.S. National Library of Medicine |access-date=9 May 2018|url-status=live|archive-url=http://archive.wikiwix.com/cache/20140813083010/https://chem.nlm.nih.gov/chemidplus/rn/7722-64-7|archive-date=13 August 2014}}</ref>

}}

| Section7 = {{Chembox Related

|OtherAnions = [[Potassium pertechnetate]]<br />[[Potassium perrhenate]]

|OtherCations = [[Sodium permanganate]]<br />[[Ammonium permanganate]]<br />[[Calcium permanganate]]<br />[[Silver permanganate]]

|OtherCompounds = [[Manganese heptoxide]]

|OtherFunction = [[Potassium hypomanganate]]<br />[[Potassium manganate]]

|OtherFunction_label = manganates

}}

}}

{{Infobox drug

|DailyMedID = Potassium_permanganate

}}

'''Potassium permanganate''' is an [[inorganic compound]] with the [[chemical formula]] KMnO₄. It is a purplish-black crystalline salt, that dissolves in water as [[potassium ion|K⁺]] and [[permanganate|{{chem|MnO|4|-}}]], an intensely pink to purple solution.

Potassium permanganate is widely used in the [[chemical industry]] and [[laboratory|laboratories]] as a strong [[oxidizing agent]], and also [[potassium permanganate (medical use)|as a medication]] for [[dermatitis]], for cleaning [[wound]]s, and general [[disinfection]]. It is on the [[WHO Model List of Essential Medicines|World Health Organization's List of Essential Medicines]].<ref name="WHO21st">{{cite book |title=World Health Organization model list of essential medicines: 21st list 2019 |vauthors=((World Health Organization)) |publisher=World Health Organization |year=2019 |location=Geneva |hdl=10665/325771 |id=WHO/MVP/EMP/IAU/2019.06. License: CC BY-NC-SA 3.0 IGO |author-link=World Health Organization |hdl-access=free}}</ref> In 2000, worldwide production was estimated at 30,000 tons.<ref name="WHO21st" />

==Properties==

Potassium permanganate is the potassium salt of the tetrahedral [[transition metal oxo complex]] [[permanganate]], in which four {{chem2|O(2-)}} ligands are bound to a [[Manganese|manganese(VII)]] center.{{cn|date=June 2023}}

===Structure===

{{chem2|KMnO4}} forms [[orthorhombic]] crystals with constants: ''a'' = 910.5&nbsp;[[picometre|pm]], ''b'' = 572.0&nbsp;pm, ''c'' = 742.5&nbsp;pm. The overall motif is similar to that for [[barium sulfate]], with which it forms [[solid solution]]s.<ref>{{cite book | title = Handbook of Preparative Inorganic Chemistry | veditors = Brauer E | publisher = Academic Press | location = New York | date = 1963 }}</ref> In the solid (as in solution), each {{chem2|MnO4−}} centre is tetrahedral. The Mn–O distances are 1.62&nbsp;Å.<ref>{{cite journal | vauthors = Palenik GJ | year = 1967 | title = Crystal structure of potassium permanganate | journal = Inorg. Chem. | volume = 6 | issue = 3| pages = 503–507 | doi = 10.1021/ic50049a015 }}</ref>

===Color===

The purplish-black color of solid potassium permanganate, and the intensely pink to purple color of its solutions, is caused by its permanganate anion, which gets its color from a strong [[Charge-transfer band|charge-transfer absorption band]] caused by excitation of electrons from oxo ligand orbitals to empty orbitals of the manganese(VII) center.<ref>{{cite book | vauthors = Miessler GL, Fischer PJ, Tarr DA |edition=5th |date=2014 |title=Inorganic Chemistry |publisher=Pearson |page=430 |isbn=978-0321811059}}</ref>

==Medical uses==

{{Main|Potassium permanganate (medical use)}}

=== Mechanism of action ===

Potassium permanganate functions as a strong [[oxidising agent]].<ref name="Derm2017">{{cite web |title=Potassium permanganate {{!}} DermNet New Zealand |url=https://www.dermnetnz.org/topics/potassium-permanganate/ |accessdate=11 October 2017 |website=www.dermnetnz.org |language=en}}</ref> Through this mechanism it results in [[disinfection]], [[astringent]] effects, and decreased smell.<ref name="Derm2017" />

=== Clinical use ===

Potassium permanganate is used for a number of [[skin condition]]s.<ref name="WHO2008" /> This includes [[tinea pedis|fungal infections of the foot]], [[impetigo]], [[pemphigus]], [[superficial wounds]], [[dermatitis]], and [[topical ulcer]]s.<ref name="BNF69">{{cite book|title=British national formulary |date=2015|author1=British Medical Association|author2-link=Royal Pharmaceutical Society|author2=Royal Pharmaceutical Society|isbn=9780857111562|page=840|edition=69|author1-link=British Medical Association}}</ref><ref name="WHO2008">{{cite book | title = WHO Model Formulary 2008 | year = 2009 | isbn = 9789241547659 | vauthors = ((World Health Organization)) | veditors = Stuart MC, Kouimtzi M, Hill SR | hdl = 10665/44053 | author-link = World Health Organization | publisher = World Health Organization | hdl-access=free | pages=295, 300}}</ref> [[Radioactive contamination]] of the skin can be cleaned with potassium permanganate and vigorous scrubbing. For topical ulcers it is used together with [[procaine benzylpenicillin]].<ref name="WHO2008" /> Typically it is used in skin conditions that produce a lot of liquid.<ref name="BNF69" /> It can be applied as a soaked dressing or a bath.<ref name="WHO20082">{{cite book |title=WHO Model Formulary 2008 |vauthors=((World Health Organization)) |publisher=World Health Organization |year=2009 |isbn=9789241547659 |veditors=Stuart MC, Kouimtzi M, Hill SR |pages=295, 300 |hdl=10665/44053 |author-link=World Health Organization}}</ref> It can be used in children and adults.<ref name="WHO2017">{{cite web |title=WHO Model Prescribing Information: Drugs Used in Skin Diseases: Antiseptic agents: Potassium permanganate |url=http://apps.who.int/medicinedocs/en/d/Jh2918e/25.2.html |url-status=dead |archive-url=https://web.archive.org/web/20090706195746/http://apps.who.int/medicinedocs/en/d/Jh2918e/25.2.html |archive-date=July 6, 2009 |accessdate=12 October 2017 |website=apps.who.int}}</ref> Petroleum jelly may be used on the nails before soaking to prevent their discoloration.<ref name="Ox2011">{{cite book | vauthors = Burge S, Wallis D | chapter = Medical Management | chapter-url = https://books.google.com/books?id=CDxsjyTSnawC&pg=PA592 |title=Oxford Handbook of Medical Dermatology |date=2011 |publisher=OUP Oxford |isbn=9780199558322 |page=592 |language=en}}</ref> For treating eczema, it is recommended using for only a few days at a time due to the possibility of it irritating the skin.<ref name="Nurse20032">{{cite web |date=5 August 2003 |title=Should potassium permanganate be used in wound care? |url=https://www.nursingtimes.net/clinical-archive/wound-care/should-potassium-permanganate-be-used-in-wound-care/205220.article |accessdate=12 October 2017 |website=Nursing Times |language=en}}</ref>

The [[U.S. Food and Drug Administration]] does not recommend its use in the crystal or tablet form. It should only be used in a diluted liquid form.<ref name="FDA20172">{{cite web |title=CFR – Code of Federal Regulations Title 21 |url=https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=250.108 |accessdate=11 October 2017 |website=www.accessdata.fda.gov}}</ref>

=== Historical use ===

Potassium permanganate was first made in the 1600s and came into common medical use at least as early as the 1800s.<ref name="Stout_2013">{{cite book | vauthors = Stout M |chapter-url=https://books.google.com/books?id=BIfEfqS8iKcC&pg=RA1-PT234 |title=The Complete Idiot's Guide to Aquaponic Gardening |date=2013 |publisher=Penguin |isbn=9781615643332 |page= 234 | chapter = Chapter 16 |language=en |url-status=live |archive-url= https://web.archive.org/web/20170116172606/https://books.google.ca/books?id=BIfEfqS8iKcC&pg=RA1-PT234 |archivedate=2017-01-16}}</ref> During [[World War I]] Canadian soldiers were given potassium permanganate (to be applied mixed with an ointment) in an effort to prevent [[sexually transmitted infections]] (resulting mostly in violet stained genitals.)<ref>{{cite book | vauthors = González-Crussi F | chapter = Pestilence and Mankind | chapter-url = https://books.google.com/books?id=bKpBZi8uG8IC&pg=PA111 |title=A Short History of Medicine |date=2008 |publisher=Random House Publishing Group |isbn=9781588368218 |page=111 |language=en}}</ref> Some have attempted to bring about an [[abortion]] by putting it in the vagina, though this is not effective.<ref>{{cite book | vauthors = Solinger R | chapter = No Extras, Curbing Fertility During the Great Depression | chapter-url = https://books.google.com/books?id=Xe6gBwAAQBAJ&pg=PA120 |title=Pregnancy and Power: A Short History of Reproductive Politics in America |date=2005 |publisher=NYU Press |isbn=9780814741191 |page=120 |language=en}}</ref><ref>{{cite book |url=https://books.google.com/books?id=SbVRAQAAMAAJ |title=Code of Federal Regulations: Record 2: 2007- |date=2008 |publisher=U.S. General Services Administration, National Archives and Records Service, Office of the Federal Register |page=178 |language=en}}</ref><ref>{{cite web |title=CFR – Code of Federal Regulations Title 21 |url=https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=250.108 |accessdate=11 October 2017 |website=www.accessdata.fda.gov}}</ref> Other historical uses have included an effort to wash out the stomach in those with [[strychnine]] or [[picrotoxin]] poisoning.<ref>{{cite web |title=Potassium permanganate definition {{!}} Drugs.com |url=https://www.drugs.com/dict/potassium-permanganate.html |accessdate=11 October 2017 |website=Drugs.com}}</ref>

=== Side effects ===

Side effects from [[Topical medication|topical]] use may include irritation of the skin and discoloration of clothing.<ref name="WHO20083">{{cite book |title=WHO Model Formulary 2008 |vauthors=((World Health Organization)) |publisher=World Health Organization |year=2009 |isbn=9789241547659 |veditors=Stuart MC, Kouimtzi M, Hill SR |pages=295, 300 |hdl=10665/44053 |author-link=World Health Organization}}</ref> A harsh burn on a child from an undissolved tablet has been reported.<ref name="Nurse2003">{{cite web |date=5 August 2003 |title=Should potassium permanganate be used in wound care? |url=https://www.nursingtimes.net/clinical-archive/wound-care/should-potassium-permanganate-be-used-in-wound-care/205220.article |accessdate=12 October 2017 |website=Nursing Times |language=en}}</ref> Higher concentration solutions can result in [[Chemical burn|chemical burns]].<ref>{{cite book | vauthors = Olson KR |url=https://books.google.com/books?id=ju7diy73Z2wC |title=Poisoning and Drug Overdose | edition = Sixth |date=2011 |publisher=McGraw Hill Professional |isbn=9780071716765 |page=121 |language=en}}</ref> Therefore, the [[British National Formulary]] recommends 100 mg be dissolved in a liter of water before use to form a 1:10,000 (0.01%) solution.<ref name="Nurse20033">{{cite web |date=5 August 2003 |title=Should potassium permanganate be used in wound care? |url=https://www.nursingtimes.net/clinical-archive/wound-care/should-potassium-permanganate-be-used-in-wound-care/205220.article |accessdate=12 October 2017 |website=Nursing Times |language=en}}</ref> <ref name="BNF692">{{cite book |author1=[[British Medical Association]] |title=British national formulary |author2=[[Royal Pharmaceutical Society]] |date=2015 |isbn=9780857111562 |edition=69 |page=840}}</ref><ref name="WHO2017222">{{cite web |title=WHO Model Prescribing Information: Drugs Used in Skin Diseases: Antiseptic agents: Potassium permanganate |url=http://apps.who.int/medicinedocs/en/d/Jh2918e/25.2.html |url-status=dead |archive-url=https://web.archive.org/web/20090706195746/http://apps.who.int/medicinedocs/en/d/Jh2918e/25.2.html |archive-date=July 6, 2009 |accessdate=12 October 2017 |website=apps.who.int}}</ref> Wrapping the dressings soaked with potassium permanganate is not recommended.{{citation needed|date=October 2023}}

Potassium permanganate is toxic if taken by mouth.<ref>{{cite book | vauthors = Maronn ML, Bree AF, Siegfried EC, Zvulunov A, Waisbourd-Zinman O, Ben-Amitai D | chapter = Principles of treatment in pediatric dermatology | veditors = Schachner LA, Hansen RC | chapter-url=https://books.google.com/books?id=tAlGLYplkacC&pg=PA131 |title=Pediatric Dermatology E-Book |date=2011 |publisher=Elsevier Health Sciences |isbn=978-0723436652 |page=131 |language=en}}</ref> Side effects may include nausea, vomiting, and shortness of breath may occur.<ref name="Patnaik_2007">{{cite book | vauthors = Patnaik P | chapter= Oxidizers | chapter-url=https://books.google.com/books?id=-CRRJBVv5d0C&pg=PA710 |title=A Comprehensive Guide to the Hazardous Properties of Chemical Substances |date=2007 |publisher=John Wiley & Sons |isbn=9780471714583 |page=710 |language=en}}</ref> If a sufficiently large amount (about 10 grams) is eaten death may occur.<ref name="Patnaik_2007" />

Concentrated solutions when drunk have resulted in [[Acute Respiratory Distress Syndrome|acute respiratory distress syndrome]] or swelling of the airway.<ref name="Schonwald_2004">{{cite book | vauthors = Schonwald S | chapter = Potassium Chloride and Potassium Permanganate | veditors = Dart RC | chapter-url=https://books.google.com/books?id=BfdighlyGiwC&pg=PA904 |title=Medical Toxicology |date=2004 |publisher=Lippincott Williams & Wilkins |isbn=9780781728454 |pages=904–905 |language=en}}</ref> Recommended measures for those who have ingested potassium permanganate include [[gastroscopy]].<ref name="Schonwald_2004" /> [[Activated charcoal (medication)|Activated charcoal]] or medications to cause vomiting are not recommended. While medications like [[ranitidine]] and [[acetylcysteine]] may be used in toxicity, evidence for this use is poor.<ref name="Schonwald_2004" />

=== Pharmaceuticals ===

In the United States the FDA requires tablets of the medication to be sold by [[Medical prescription|prescription]].<ref name="FDA2017">{{cite web |title=CFR – Code of Federal Regulations Title 21 |url=https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfcfr/CFRSearch.cfm?fr=250.108 |accessdate=11 October 2017 |website=www.accessdata.fda.gov}}</ref> Potassium permanganate, however, does not have FDA approved uses and therefore non medical grade potassium permanganate is sometimes used for medical purposes.^{[''[[Wikipedia:Citation needed|citation needed]]'']}

It is available under a number of [[brand names]] including Permasol, Koi Med Tricho-Ex, and Kalii permanganas RFF.<ref>{{cite web |title=Potassium Permanganate - Drugs.com |url=https://www.drugs.com/international/potassium-permanganate.html |accessdate=11 October 2017 |website=Drugs.com}}</ref> It is occasionally called "Condy's crystals".<ref name="Derm20172">{{cite web |title=Potassium permanganate | work = DermNet New Zealand |url=https://www.dermnetnz.org/topics/potassium-permanganate/ |accessdate=11 October 2017 |language=en}}</ref>

=== Veterinary medicine ===

Potassium permanganate may be used to prevent the spread of [[glanders]] among horses.<ref>{{cite book | vauthors = Scott DW, Miller WH | chapter = Bacterial Skin Diseases | chapter-url = https://books.google.com/books?id=f0-v1vOq3x4C&pg=PA168 |title=Equine Dermatology – E-Book | date = 2010 | publisher = Elsevier Health Sciences |isbn=978-1437709216 |page=168 |language=en}}</ref>

==Industrial and other uses==

Almost all applications of potassium permanganate exploit its oxidizing properties.<ref name="Ullmann" /> As a strong oxidant that does not generate toxic byproducts, KMnO₄ has many niche uses.{{cn|date=June 2023}}

===Water treatment===

Potassium permanganate is used extensively in the water treatment industry. It is used as a regeneration chemical to remove [[iron]] and [[hydrogen sulfide]] (rotten egg smell) from [[water well|well]] water via a "manganese greensand" filter. "Pot-Perm" is also obtainable at [[swimming pool|pool]] supply stores and is used additionally to treat wastewater. Historically it was used to disinfect drinking water<ref>{{cite book|isbn = 978-0-309-02931-5|page = 98|url = https://books.google.com/books?id=uVlQ_TUP-f0C&pg=PA98I|title=Drinking water and health, Volume 2|author=Assembly of Life Sciences (U.S.). Safe Drinking Water Committee|publisher = National Academies Press|year = 1977|access-date = 2016-09-13}}</ref><ref>{{cite web | vauthors = Downey R, Barrington M | date = 28 February 2005 |url=http://www.northernadvocate.co.nz/local/news/red-faces-over-pink-water/3625948/ |archive-url=https://web.archive.org/web/20110719003200/http://www.northernadvocate.co.nz/local/news/red-faces-over-pink-water/3625948/ |archive-date=2011-07-19 | title = Red faces over pink water | work = The Northern Advocate }}</ref> and can turn the water pink.<ref>{{cite news|title=Onoway apologizes for 'alarming' pink tap water|url=http://www.cbc.ca/news/canada/edmonton/onoway-water-chemical-pink-1.4013808|access-date=8 March 2017|work=[[CBC News]]|date=7 March 2017|url-status=live|archive-url=https://web.archive.org/web/20170307225245/http://www.cbc.ca/news/canada/edmonton/onoway-water-chemical-pink-1.4013808|archive-date=7 March 2017}}</ref> Modern hiking and survivalist guides advise against using potassium permanganate in the field because it is difficult to dose correctly.<ref>{{cite book|title=Trinkwasserversorgung in Extremsituationen|author= Johannes Vogel |date= 2014 |publisher= Paul Pietsch Verlage GmbH|isbn=978-3613507845|language=German}}</ref> It currently finds application in the control of nuisance organisms such as [[zebra mussel]]s in fresh water collection and treatment systems.<ref>{{cite web | url = https://www.epa.gov/dwreginfo/stage-1-and-stage-2-disinfectants-and-disinfection-byproducts-rules | title = EPA Guidance Manual Alternative Disinfectants and Oxidants | date = 13 October 2015 | archive-url = https://web.archive.org/web/20161001044131/https://www.epa.gov/dwreginfo/stage-1-and-stage-2-disinfectants-and-disinfection-byproducts-rules | archive-date=2016-10-01 | publisher = U.S. Environmental Protection Agency }}</ref>

===Synthesis of organic compounds===<!-- [[Baeyer's reagent]] redirects to this section -->

[[File:KMnO4 in H2O.jpg|thumb|upright|A solution of KMnO₄ in water, in a [[volumetric flask]]]]

A major application of KMnO₄ is as a reagent for the synthesis of organic compounds.<ref>{{cite journal| vauthors = Fatiadi A |title = The Classical Permanganate Ion: Still a Novel Oxidant in Organic Chemistry|year = 1987|journal = [[Synthesis (journal)|Synthesis]]|volume = 1987|issue = 2|pages = 85–127|doi = 10.1055/s-1987-27859| s2cid=94121246 }}</ref> Significant amounts are required for the synthesis of [[ascorbic acid]], [[chloramphenicol]], [[saccharin]], [[isonicotinic acid]], and [[pyrazinoic acid]].<ref name="Ullmann" />

KMnO₄ is used in [[qualitative organic analysis]] to test for the presence of [[Saturated and unsaturated compounds|unsaturation]]. It is sometimes referred to as '''Baeyer's reagent''' after the German organic chemist [[Adolf von Baeyer]]. The reagent is an alkaline solution of potassium permanganate. Reaction with double or triple bonds (-C=C- or -C≡C-) causes the color to fade from purplish-pink to brown. [[Aldehyde]]s and [[formic acid]] (and [[formate]]s) also give a positive test.<ref>{{cite web | vauthors = Glagovich N | date = 2013 | work = Department of Chemistry and Biochemistry | publisher = Central Connecticut State University |url= http://www.chemistry.ccsu.edu/glagovich/teaching/316/qualanal/tests/baeyertest.html|title=Baeyer Test |access-date=9 May 2018 |url-status=dead |archive-url= https://web.archive.org/web/20130124005821/http://www.chemistry.ccsu.edu/glagovich/teaching/316/qualanal/tests/baeyertest.html |archive-date=24 January 2013}}</ref> The test is antiquated.

[[Image:Baeyer's Probe Alkenes V.2.svg|center|550px|Baeyer's reagent reaction]]

KMnO₄ solution is a common [[thin layer chromatography]] (TLC) stain for the detection of oxidizable functional groups, such as alcohols, aldehydes, alkenes, and ketones. Such compounds result in a white to orange spot on TLC plates.<ref>Thin Layer Chromatography stains http://www.reachdevices.com/TLC_stains.html</ref><ref>Jork, H., Funk, W., Fischer, W., Wimmer, H. (1990): Thin-Layer Chromatography: Reagents and Detection Methods, Volume 1a, VCH, Weinheim, {{ISBN|3-527-278834}}</ref><ref>Jork, H., Funk, W., Fischer, W., Wimmer, H. (1994): Thin-Layer Chromatography: Reagents and Detection Methods, Volume 1b, VCH, Weinheim</ref>

===Analytical use===

Potassium permanganate can be used to quantitatively determine the total oxidizable organic material in an aqueous sample. The value determined is known as the ''permanganate value.'' In [[analytical chemistry]], a standardized [[aqueous]] solution of KMnO₄ is sometimes used as an oxidizing [[titration|titrant]] for [[redox titration]]s ([[permanganometry]]). As potassium permanganate is titrated, the solution becomes a light shade of purple, which darkens as excess of the titrant is added to the solution. In a related way, it is used as a [[reagent]] to determine the [[Kappa number]] of wood pulp. For the standardization of KMnO₄ solutions, reduction by [[oxalic acid]] is often used.<ref>{{cite journal|title = Revising the Mechanism of the Permanganate/Oxalate Reaction|vauthors=Kovacs KA, Grof P, Burai L, Riedel M |journal = J. Phys. Chem. A|doi = 10.1021/jp047061u|year = 2004|volume = 108|page = 11026|issue = 50|bibcode = 2004JPCA..10811026K}}</ref> In agricultural chemistry, it is used for estimation of active [[carbon]]<!-- not quite the meaning of the [[active carbon]] article --> in soil.<ref>{{cite web |url= https://vro.agriculture.vic.gov.au/dpi/vro/vrosite.nsf/pages/soilhealth_potassium-permanganate |title= Quick Reference Guide: Potassium Permanganate Test for Active Carbon |website= Agriculture Victoria—Victorian Resources Online |publisher= [[Victoria, Australia]]}}</ref>

Aqueous, acidic solutions of KMnO₄ are used to collect gaseous [[mercury (element)|mercury]] in flue gas during stationary source emissions testing.<ref>[[Code of Federal Regulations]](7-1-07) Edition, [[Title 40 of the United States Code|Title 40]], Part 60, Appendix A-8, Method 29, Section 7.3.1</ref>

In [[histology]], potassium permanganate was used as a bleaching agent.<ref name="Picken_2010">{{cite journal | vauthors = Picken MM | title = Amyloidosis-where are we now and where are we heading? | journal = Archives of Pathology & Laboratory Medicine | volume = 134 | issue = 4 | pages = 545–551 | date = April 2010 | pmid = 20367306 | doi = 10.5858/134.4.545}}</ref><ref name="Murphy_2001">{{cite journal | vauthors = Murphy CL, Eulitz M, Hrncic R, Sletten K, Westermark P, Williams T, Macy SD, Wooliver C, Wall J, Weiss DT, Solomon A | title = Chemical typing of amyloid protein contained in formalin-fixed paraffin-embedded biopsy specimens | journal = American Journal of Clinical Pathology | volume = 116 | issue = 1 | pages = 135–142 | date = July 2001 | pmid = 11447744 | doi = 10.1309/TWBM-8L4E-VK22-FRH5 | doi-access = free}}</ref>

===Fruit preservation===

[[Ethylene]] absorbents extend storage time of [[banana]]s even at high temperatures. This effect can be exploited by packing bananas in [[polyethylene]] together with potassium permanganate. By removing ethylene by oxidation, the permanganate delays the ripening, increasing the fruit's shelf life up to 4 weeks without the need for refrigeration.<ref>{{cite journal| vauthors = Scott KJ, McGlasson WB, Roberts EA |title=Potassium Permanganate as an Ethylene Absorbent in Polyethylene Bags to Delay the Ripening of Bananas During Storage|journal= Australian Journal of Experimental Agriculture and Animal Husbandry |doi=10.1071/EA9700237|volume=10|issue=43|page= 237|year=1970}}</ref><ref>{{cite journal| vauthors = Scott KJ, Blake, JR, Stracha, G, Tugwell, BL and McGlasson WB |year=1971|title= Transport of Bananas at Ambient Temperatures using Polyethylene Bags|journal= Tropical Agriculture (Trinidad)|volume= 48|pages= 163–165}}</ref><ref>{{cite journal| vauthors = Scott KJ, Gandanegara S |year=1974|title= Effect of Temperature on the Storage Life of bananas Held in Polyethylene Bags with an Ethylene Absorbent|journal= Tropical Agriculture (Trinidad)|volume= 51|pages=23–26}}</ref>

The chemical reaction, in which [[ethylene]] (C₂H₄) is oxidised by potassium permanganate (KMnO₄) to [[carbon dioxide]] (CO₂), [[manganese oxide]] (MnO₂) and [[potassium hydroxide]] (KOH), in the presence of water, is presented as follows:<ref>{{cite journal | title=Current scenario of adsorbent materials used in ethylene scavenging systems to extend fruit and vegetable postharvest life |vauthors=Álvarez-Hernández MH, Artés-Hernández F, Ávalos-Belmontes F, Castillo- Campohermoso MA, Contreras-Esquivel JC, Ventura-Sobrevilla JM, Martínez-Hernández GB | journal=Food Bioproc Technol | date=2018 | volume=11 |issue=3 | pages=511–525 | doi=10.1007/s11947-018-2076-7}}</ref>

3 C₂H₄ + 12 KMnO₄ + 2 H₂O → 6 CO₂ + 2 H₂O + 12 MnO₂ + 12 KOH

===Survival kits===

Potassium permanganate is sometimes included in survival kits: as a [[hypergolic]] fire starter (when mixed with [[glycerol]] antifreeze from a car radiator);<ref name="Bob Gillis and Dino Labiste">{{cite web |url=http://www.primitiveways.com/chemical_fire.html |title=Fire by Chemical Reaction | vauthors = Gillis B, Labiste D |url-status=live |archive-url= https://web.archive.org/web/20150924081745/http://www.primitiveways.com/chemical_fire.html |archive-date=2015-09-24 | work = PrimitiveWays }}</ref><ref>{{cite web|url=http://pssurvival.com/PS/Chemistry/Uses_of_Potassium_Permanganate_2010.pdf#page=1|title=Potassium Permanganate |website=Pole Shift Survival Information |access-date=9 May 2018|url-status=dead|archive-url=https://web.archive.org/web/20160804172658/http://www.pssurvival.com/PS/Chemistry/Uses_of_Potassium_Permanganate_2010.pdf#page=1|archive-date=4 August 2016}}</ref><ref>{{cite web |url=http://thesurvivalcache.weebly.com/thesurvivalcaches-blog/making-fire-with-potassium-permanganate-and-glycerin |title=Making Fire with Potassium Permanganate and Glycerin |work=thesurvivalcache |date=3 November 2012 |access-date=13 September 2016 |url-status=live |archive-url=https://web.archive.org/web/20160513141530/http://thesurvivalcache.weebly.com/thesurvivalcaches-blog/making-fire-with-potassium-permanganate-and-glycerin |archive-date=13 May 2016}}</ref> as a water sterilizer; and for creating distress signals on snow.<ref>{{cite journal |url=http://paperspast.natlib.govt.nz/cgi-bin/paperspast?a=d&d=EP19360507.2.20 |title=Distress Signals |journal=Evening Post |volume=CXXI |issue=107 |date=7 May 1936 |page=5 |url-status=live |archive-url=https://web.archive.org/web/20111105110817/http://paperspast.natlib.govt.nz/cgi-bin/paperspast?a=d&d=EP19360507.2.20 |archive-date=5 November 2011}}</ref>

===Fire service===

Potassium permanganate is added to "plastic sphere dispensers" to create backfires, burnouts, and [[controlled burn]]s. Polymer spheres resembling [[Table tennis#Ball|ping-pong balls]] containing small amounts of permanganate are injected with [[ethylene glycol]] and projected towards the area where ignition is desired, where they spontaneously ignite seconds later.<ref name=usfs>{{cite web|url=http://www.fs.fed.us/eng/aerial_ign/plsphere/describe.htm| work = Missoula Technology and Development Center | publisher = USDA Forest Service | title = Aerial Ignition, Plastic Sphere Dispenser Description |access-date=9 May 2018|url-status=dead |archive-url= https://web.archive.org/web/20160426215606/http://www.fs.fed.us/eng/aerial_ign/plsphere/describe.htm |archive-date=26 April 2016}}</ref><ref name=dj>{{Cite episode |title= Wetland Warrior |series=[[Dirty Jobs]]|season=6 |number=2}}</ref> Both handheld{{r|dj}} helicopter-{{r|usfs}} unmanned aircraft systems (UAS) or boat-mounted{{r|dj}} plastic sphere dispensers are used.

===Other uses===

Potassium permanganate is one of the principal chemicals used in the film and television industries to "age" props and set dressings. Its ready conversion to brown [[Manganese dioxide|MnO₂]] creates "hundred-year-old" or "ancient" looks on [[hessian cloth]] (burlap), ropes, timber and glass.<ref>{{cite journal|url = http://www.paintpro.net/Articles/PP201/PP201-Contractor_Profile.cfm|title = Victor DeLor contractor profile|access-date = 2009-11-12| vauthors = Brody E |journal = PaintPRO |volume = 2|issue = 1|date = February 2000|quote = One of the techniques DeLor is known for among designers and clients is the special effects he creates with various chemical solutions. When applied to wood surfaces, these chemicals give a weathered appearance to new wood. ... To achieve the aesthetic on interior surfaces, DeLor often uses a mixture of water and potassium permanganate, a dry powder chemical.|url-status = live|archive-url = https://web.archive.org/web/20080723213651/http://www.paintpro.net/Articles/PP201/PP201-Contractor_Profile.cfm|archive-date = 2008-07-23}}</ref>

Potassium permanganate can be used to oxidize [[cocaine paste]] to purify it and increase its stability. This led to the [[Drug Enforcement Administration]] launching Operation Purple in 2000, with the goal of monitoring the world supply of potassium permanganate; however, potassium permanganate derivatives and substitutes were soon used thereafter to avoid the operation.<ref>{{cite news |url=https://www.vice.com/en_ca/article/vdpb4y/the-cash-is-in-the-cut |publisher=[[Vice Media]] |title=The Terrifying Substances People Put in Cocaine | vauthors = Gosmer K, Vammen M |date=March 10, 2014}}</ref>

Potassium permanganate is used as an [[oxidizing agent]] in the synthesis of [[cocaine]] and [[methcathinone]].<ref>{{cite journal | vauthors = Binder R, Machata G, Stead H | title = [Analysis of potassium permanganate as addictive drug "precursor"] | journal = Archiv Fur Kriminologie | volume = 211 | issue = 5–6 | pages = 160–165 | date = May 2003 | pmid = 12872685 }}</ref>

Potassium permanganate is one of a number of possible treatments for ''[[Ichthyophthirius multifiliis]]'' (commonly known as "ich"), a parasite that infects and usually kills freshwater aquarium fish.

==History==

In 1659, [[Johann Rudolf Glauber]] fused a mixture of the mineral [[pyrolusite]] (manganese dioxide, MnO₂) and [[potassium carbonate]] to obtain a material that, when dissolved in water, gave a green solution ([[potassium manganate]]) which slowly shifted to violet and then finally red.<ref>Glauber, Johann Rudolph, ''Prosperitas Germaniae'' (The prosperity of Germany), part 3 (Amsterdam, (Netherlands): Johann Jansson, 1659), pp. 93–94. From pp. 93–94: ''" … donec tandem Magnesiam istam nitro fixo permixtam, in crucibulo forti coctione a nitro reseratam vidi, unde elegans color purpureus provenit, massam hanc effusam in pulvere redegi, aqua calida extraxi, per filtrum liquorem transmisi. Tandem vero elegantissimum purpureum, igneumque liquorem accepi, qui fere singulis horis in frigore tantummodo consistens colorem permutavit, sic ut jam viridis, jam caerulei, jam sanguinei coloris sponte sua factus sit, mox iterum alios elegantissimos colores receperit."'' ( … until finally I saw [that] by mixing that ''magnesia'' [i.e., ''magnesia nigra'', [[pyrolusite]], the ore containing [[manganese dioxide]] ] with fixed [[niter]] [i.e., inert niter, potassium carbonate], by cooking [it] in a strong crucible, [the colored compound was] released by the niter, whence a fine purple color arises; this mass [was] poured out, reduced to powder, extracted with hot water, [and] the solution passed through a filter. Then I got a truly most elegant, purple, and fiery solution, which nearly every hour ([while] standing just in the cold) changed color, so that it was spontaneously made now green, now blue, now red in color; soon again it received other most elegant colors.) {{cite web | vauthors = Glauber JR | title = Prosperitatis Germaniae pars .... 3: In qua Salpetrae ex variis ubiq, obviis subiectis facillime atque copiose extrahendi modus traditur. Eiusve utilitates summae declarantur | trans-title = Part of the Prosperity of Germany .... 3: In which the method of extracting saltpeter from various everywhere, in the most convenient and abundant manner, is given. His interests are clearly stated | language = Latin | url = https://www.digitale-sammlungen.de/en/view/bsb10915847?page=100 | via = Bavarian State Library | archive-url = https://web.archive.org/web/20161220151825/http://reader.digitale-sammlungen.de/en/fs1/object/display/bsb10915847_00100.html | archive-date=2016-12-20 }} Translated in: {{cite book | vauthors = Glauber JR | translator-last1= Packe C | title = The Works of the Highly Experienced and Famous Chymist, John Rudolph Glauber | location = London, England | publisher = Thomas Millbourn | date = 1689 | url = https://archive.org/stream/worksofhighlyexp00glau#page/352/mode/2up | page = 353 | archive-url = https://web.archive.org/web/20120107040133/http://www.archive.org/stream/worksofhighlyexp00glau | archive-date=2012-01-07 }}</ref> The reaction that produced the color changes that Glauber observed in his solution of potassium permanganate and potassium manganate (K₂MnO₄) is now known as the "[[chemical chameleon]]".<ref>{{Cite web |date=2024-01-19 |title=How to use Chameleon Pigment for Chameleon Paint? |url=https://www.kingchroma.com/uses/how-to-use-chameleon-pigment-for-chameleon-paint |access-date=2024-06-07 |language=en-US}}</ref> This report represents the first description of the production of potassium permanganate.<ref>{{cite book | vauthors = Weeks ME | veditors = Leicester HM | title = Discovery of the Elements | edition = 6th | location = Easton, Pennsylvania | publisher = Journal of Chemical Education | date = 1956 | url = https://archive.org/stream/discoveryoftheel002045mbp#page/n185/mode/2up | pages = 172–173 }}</ref> Just under 200 years later, London chemist [[Henry Bollmann Condy]] had an interest in disinfectants; he found that fusing pyrolusite with [[sodium hydroxide]] (NaOH) and dissolving it in water produced a solution with disinfectant properties. He patented this solution, and marketed it as 'Condy's Fluid'. Although effective, the solution was not very stable. This was overcome by using [[potassium hydroxide]] (KOH) rather than NaOH. This was more stable, and had the advantage of easy conversion to the equally effective potassium permanganate crystals. This crystalline material was known as 'Condy's crystals' or 'Condy's powder'. Potassium permanganate was comparatively easy to manufacture, so Condy was subsequently forced to spend considerable time in litigation to stop competitors from marketing similar products.<ref>{{cite journal|url=http://www.paperspast.natlib.govt.nz/cgi-bin/paperspast?a=d&d=OW19000802.2.357|title=Important Trade Mark Case|journal=Otago Witness|volume=2|issue=2420|date=2 August 1900|page=53|url-status=live|archive-url=https://web.archive.org/web/20160304003229/http://paperspast.natlib.govt.nz/cgi-bin/paperspast?a=d&d=OW19000802.2.357|archive-date=4 March 2016}}</ref>

Early photographers used it as a component of [[flash powder]]. It is now replaced with other oxidizers, due to the instability of permanganate mixtures.{{cn|date=June 2023}}

== Preparation ==

Potassium permanganate is produced industrially from [[manganese dioxide]], which also occurs as the mineral [[pyrolusite]]. In 2000, worldwide production was estimated at 30,000 tonnes.<ref name="Ullmann">{{Ullmann|vauthors = Reidies AH |year=2002|title=Manganese Compounds|doi=10.1002/14356007.a16_123}}</ref> The MnO₂ is fused with [[potassium hydroxide]] and heated in [[air]] or with another source of oxygen, like [[potassium nitrate]] or [[potassium chlorate]].<ref name="Ullmann"/> This process gives [[potassium manganate]]:

:<chem>2 MnO2 + 4 KOH + O2 -> 2 K2MnO4 + 2 H2O</chem>

With sodium hydroxide, the end product is not [[sodium manganate]] but an Mn(V) compound, which is one reason why the potassium permanganate is more commonly used than [[sodium permanganate]]. Furthermore, the potassium salt crystallizes better.<ref name="Ullmann"/>

The potassium manganate is then converted into permanganate by [[electrolysis|electrolytic oxidation]] in alkaline media:

:<chem>2 K2MnO4 + 2 H2O -> 2 KMnO4 + 2 KOH + H2</chem>

===Other methods===

Although of no commercial importance, potassium manganate can be oxidized by [[chlorine]] or by [[disproportionation]] under acidic conditions.<ref>{{cite book | vauthors = Walton HF | date = 1948 | title = Inorganic Preparations | location = New York | publisher = Prentice-Hall | pages = 150–151}}</ref> The chlorine oxidation reaction is

:<chem>2 K2MnO4 + Cl2 -> 2 KMnO4 + 2 KCl</chem>

and the acid-induced [[disproportionation reaction]] may be written as

:<chem>3 K2MnO4 + 4 HCl -> 2 KMnO4 + MnO2 + 2 H2O + 4 KCl</chem>

A weak acid such as [[carbonic acid]] is sufficient for this reaction:

:<chem>3 K2MnO4 + 2 CO2 -> 2 KMnO4 + 2 K2CO3 + MnO2</chem>

Permanganate salts may also be generated by treating a solution of Mn²⁺ ions with strong oxidants such as [[lead dioxide]] (PbO₂), [[sodium bismuthate]] (NaBiO₃), or [[peroxydisulfate]]. [[Qualitative inorganic analysis|Tests]] for the presence of manganese exploit the vivid violet color of permanganate produced by these reagents.

==Reactions==

===Organic chemistry===

Dilute solutions of KMnO₄ convert [[alkene]]s into [[diol]]s. This behaviour is also used as a [[qualitative chemical analysis|qualitative]] [[chemical test|test]] for the presence of double or triple bonds in a molecule, since the reaction decolorizes the initially purple [[permanganate]] solution and generates a brown precipitate (MnO₂). In this context, it is sometimes called ''Baeyer's reagent''. However, [[bromine]] serves better in measuring unsaturation (double or triple bonds) quantitatively, since KMnO₄, being a very strong [[oxidizing agent]], can react with a variety of groups.

Under acidic conditions, the alkene double bond is cleaved to give the appropriate [[carboxylic acid]]:<ref>{{OrgSynth|title = Carboxylic Acids from the Oxidation of Terminal Alkenes by Permanganate: Nonadecanoic Acid| vauthors = Lee DG, Lamb SE, Chang VS |collvol = 7 |collvolpages = 397 |year = 1990 |prep = cv7p0397}}</ref>

:<chem>CH3(CH2)17CH=CH2 + 2 KMnO4 + 3 H2SO4 -> CH3(CH2)17COOH + CO2 + 4 H2O + K2SO4 + 2 MnSO4</chem>

Potassium permanganate oxidizes aldehydes to carboxylic acids, illustrated by the conversion of ''n''-[[heptanal]] to heptanoic acid:<ref>{{OrgSynth| vauthors = Ruhoff JR |title = ''n''-Heptanoic acid |collvol = 2 |collvolpages = 315 |prep = cv2p0315}}</ref>

:<chem>5 C6H13CHO + 2 KMnO4 + 3 H2SO4 -> 5 C6H13COOH + 3 H2O + K2SO4 + 2 MnSO4</chem>

Even an alkyl group (with a benzylic hydrogen) on an [[aromatic ring]] is oxidized, e.g. [[toluene]] to [[benzoic acid]].<ref>{{cite journal | vauthors = Gardner KA, Mayer JM | title = Understanding C-H bond oxidations: H. and H- transfer in the oxidation of toluene by permanganate | journal = Science | volume = 269 | issue = 5232 | pages = 1849–1851 | date = September 1995 | pmid = 7569922 | doi = 10.1126/science.7569922 | bibcode = 1995Sci...269.1849G}}</ref>

:<chem>5 C6H5CH3 + 6 KMnO4 + 9 H2SO4 -> 5 C6H5COOH + 14 H2O + 3 K2SO4 + 6 MnSO4</chem>

Glycols and [[polyol]]s are highly reactive toward KMnO₄. For example, addition of potassium permanganate to an aqueous solution of [[sugar]] and [[sodium hydroxide]] produces the [[chemical chameleon]] reaction, which involves dramatic color changes associated with the various oxidation states of [[manganese]]. A related vigorous reaction is exploited as a fire starter in survival kits. For example, a mixture of potassium permanganate and [[glycerol]] or pulverized [[glucose]] ignites readily.<ref name="Bob Gillis and Dino Labiste"/> Its sterilizing properties are another reason for inclusion of KMnO₄ in a survival kit.{{cn|date=June 2023}}

===Ion exchange===

Treating a mixture of aqueous potassium permanganate with a [[quaternary ammonium salt]] results in ion exchange, precipitating the quat salt of permanganate. Solutions of these salts are sometimes soluble in organic solvents:<ref>{{cite journal | title = Purple benzene: Solubilization of anions in organic solvents | vauthors = Herriott AW | journal = J. Chem. Educ. | year = 1977 | volume = 54 | issue = 4 | page = 229 | doi = 10.1021/ed054p229.1| bibcode = 1977JChEd..54Q.229H}}</ref>

:<chem>KMnO4 + R4NCl -> R4NMnO4 + KCl</chem>

Similarly, addition of a [[crown ether]] also gives a lipophilic salt.<ref>{{Cite journal | vauthors = Doheny Jr AJ, Ganem B | title = Purple benzene revisited | journal = J. Chem. Educ. | year = 1980 | volume = 57 | page = 308 | doi = 10.1021/ed057p308.1 | issue = 4|bibcode=1980JChEd..57..308D}}</ref>

===Reaction with acids and bases===

Permanganate reacts with concentrated [[hydrochloric acid]] to give [[chlorine]] and manganese(II):

:<chem>2 KMnO4 + 16 HCl -> 2 MnCl2 + 5 Cl2 + 2 KCl + 8 H2O</chem>

In [[pH|neutral]] solution, permanganate slowly reduces to [[manganese dioxide]] (MnO₂). This is the material that stains one's skin when handling KMnO₄.

KMnO₄ reduces in [[alkaline]] solution to give green [[potassium manganate|K₂MnO₄]]:<ref>{{cite book | doi = 10.1002/9780470132425.ch11 | vauthors = Nyholm RS, Woolliams PR | title = Inorganic Syntheses |author-link=Ronald Sydney Nyholm | chapter = Manganates (VI) | year = 1968 | volume = 11 | pages = 56–61 | isbn = 978-0-470-13242-5}}</ref>

:<chem>4 KMnO4 + 4 KOH -> 4 K2MnO4 + O2 + 2 H2O</chem>

This reaction illustrates the relatively rare role of hydroxide as a reducing agent.

Addition of concentrated sulfuric acid to potassium permanganate gives [[manganese(VII) oxide|Mn₂O₇]].<ref>{{cite book | vauthors = Cotton FA, Wilkinson G, Murillo CA, Bochmann M | date = 1999 | title = Advanced Inorganic Chemistry | edition = 6th | publisher = Wiley-VCH | isbn = 0-471-19957-5}}</ref> Although no reaction may be apparent, the vapor over the mixture will ignite paper impregnated with alcohol. Potassium permanganate and sulfuric acid react to produce some [[ozone]], which has a high oxidizing power and rapidly oxidizes the alcohol, causing it to combust. As the reaction also produces explosive Mn₂O₇, this should only be attempted with great caution.<ref>{{cite journal| vauthors = Barthel H, Duvinage B |title = Clemens Winkler. His Experiments with Ozone in 1892|journal = Praxis der Naturwissenschaften, Chemie |year = 2000|volume = 49|pages = 18ff}}</ref><ref>{{cite journal | vauthors = Dzhabiev TS, Denisov NN, Moiseev DN, Shilov AE |title = Formation of Ozone During the Reduction of Potassium Permanganate in Sulfuric Acid Solutions|journal = Russian Journal of Physical Chemistry|year = 2005|volume = 79|pages = 1755–1760}}</ref>

===Thermal decomposition===

Solid potassium [[permanganate]] decomposes when heated:

:<chem>2 KMnO4 -> K2MnO4 + MnO2 + O2</chem>

It is a redox reaction.

==Safety and handling==

Potassium permanganate poses risks as an [[oxidizer]].<ref name="Bretherick_2007">{{cite book | vauthors = Bretherick L, Urben PG, Pitt MJ | year = 2007 | title = Bretherick's Handbook of Reactive Chemical Hazards | edition = 7th | volume = 1| publisher = Elsevier Academic Press| isbn = 978-0-12-373945-2 | pages = 1811–7| title-link = Bretherick's Handbook of Reactive Chemical Hazards }}</ref> Contact with skin can cause skin irritation and in some cases severe allergic reaction. It can also result in discoloration and clothing stains.<ref>{{cite web |url= https://www.livestrong.com/article/74289-remove-potassium-permanganate/ |title=How to Remove Potassium Permanganate| vauthors = Griffin S |website=livestrong.com|access-date=9 May 2018|url-status=live|archive-url= https://web.archive.org/web/20180413125030/https://www.livestrong.com/article/74289-remove-potassium-permanganate/|archive-date=13 April 2018}}</ref>

== References ==

{{Reflist}}

== Further reading ==

{{refbegin}}

* [https://www.gutenberg.org/ebooks/74154 "The reaction between manganese dioxide and potassium permanganate"] (1893) by A. J. Hopkins

* {{cite web | url = http://www.npi.gov.au/resource/manganese-compounds | work = National Pollutant Inventory | title = Manganese and compounds Fact Sheet | publisher = Department of Climate Change, Energy, the Environment and Water | location = Australia}}

* {{cite web | vauthors = Lazur AM |url=http://edis.ifas.ufl.edu/fa032 |archive-url=https://web.archive.org/web/20110606090007/http://edis.ifas.ufl.edu/fa032 |archive-date=2011-06-06 | title = The use of potassium permanganate in fish ponds | date = 2009 | work = IFAS Extension | location = Gainesville, FL | publisher = University of Florida}}

{{refend}}

== External links ==

* {{ICSC|0672|06}}

{{Permanganates}}

{{Potassium compounds}}

{{Antiseptics and disinfectants}}

{{Antidotes}}

{{Organic reactions}}

{{portal bar|Medicine}}

[[Category:Potassium compounds]]

[[Category:Permanganates]]

[[Category:Oxidizing agents]]

[[Category:Disinfectants]]

[[Category:Abortifacients]]

[[Category:Pyrotechnic oxidizers]]

[[Category:Photographic chemicals]]

[[Category:Articles containing video clips]]

[[Category:World Health Organization essential medicines]]

[[Category:Multiple Chemboxes|X]]