Rubidium permanganate
{{Chembox
| ImageFile= Caesiumpermanganat.png
|Section3={{Chembox Structure
| CrystalStruct = orthorhombic
| SpaceGroup = Pnma (Nr. 62)
| LattConst_a =954.11 pm
|LattConst_b=573.926 pm
| LattConst_c=763.63 pm
}}
|Section1={{Chembox Identifiers
| CASNo = 13465-49-1
| PubChem = 23674440
| ChemSpiderID = 13389592
| StdInChI=1S/Mn.4O.Rb/q;;;;-1;+1
| StdInChIKey = UJCOPKFKNRFWHO-UHFFFAOYSA-N
| SMILES=[Rb+].[O-][Mn](=O)(=O)=O
}}
|Section2={{Chembox Properties
| Formula=RbMnO4
| Appearance= purple crystals{{citation|author=R. Hoppe, D. Fischer, J. Schneider|date=1999|doi=10.1002/(SICI)1521-3749(199907)625:7<1135::AID-ZAAC1135>3.0.CO;2-L|issue=7|pages=1521–3749|periodical=Zeitschrift für anorganische und allgemeine Chemie|title=Zur Kenntnis von Oxyden A[MO4]: Über LiMnO4, KMnO4, RbMnO4, CsMnO4 sowie RbIO4 und CsIO4. (– Was heißt eigentlich "Die Kristallstruktur von …"? –)|volume=625}}
| MolarMass = 204.404
| Density= 3.325 g·cm−3Dale L. Perry, Sidney L. Phillips: Handbook of inorganic compounds. CRC Press, 1995, ISBN 978-0-8493-8671-8, S. 336 ({{Google books|0fT4wfhF1AsC||page=336}}).
| MeltingPt= 295 °C (decomposes)
| Solubility= 10.6 g·l−1 （19 °C）
}}
| Section8={{Chembox Related
| OtherCations =lithium permanganate
sodium permanganate
potassium permanganate
ammonium permanganate
caesium permanganate
| OtherAnions=rubidium perchlorate
rubidium periodate
rubidium pertechnetate
}}
}}
Rubidium permanganate is the permanganate salt of rubidium, with the chemical formula {{chem|RbMnO|4}}.
Preparation
Rubidium permanganate can be formed by the reaction of potassium permanganate and rubidium chloride:{{citation|author=Michael W. Beck, Michael E. Brown|date=1983|doi=10.1016/0040-6031(83)80022-7|issue=2–3|pages=197–212|periodical=Thermochimica Acta|title=Thermal analysis of antimony/potassium permanganate pyrotechnic compositions|url=http://eprints.ru.ac.za/252/3/PUBLICATIONS/TCA65.pdf|archive-url=https://web.archive.org/web/20131029201832/http://eprints.ru.ac.za/252/3/PUBLICATIONS/TCA65.pdf|archive-date=2013-10-29|volume=65}}{{citation|author=P. J. Herley, E. G. Prout|date=1960|doi=10.1021/j100834a503|issue=5|pages=675–677|periodical=The Journal of Physical Chemistry|title=The Thermal Decomposition of Rubidium Permanganate|volume=64}}
:{{chem2| RbCl + KMnO4 -> KCl + RbMnO4 ↓ }}
Properties
= Physical =
Rubidium permanganate is soluble in water with a solubility of 6.03 g/L at 7 °C,{{citation|author=Aterton Seidell|date=1940|pages=1438|title=Solubilities of Organic Compounds|url=http://www.archive.org/stream/solubilitiesofor023311mbp#page/n933/mode/2up |volume=1}} 10.6 g/L at 19 °C, and 46.8 g/L at 60 °C.{{citation|author=Austin M. Patterson|date=1906|doi=10.1021/ja01978a009|issue=12|pages=1734–1736|periodical=Journal of the American Chemical Society|title=Solubilities of Permanganates of the Alkali Metals|volume=28|url=https://zenodo.org/record/1428880 }} Its crystal structure is orthorhombic, the same as caesium permanganate, ammonium permanganate and potassium permanganate.
= Chemical =
Similar to potassium permanganate, the two-step decomposition of rubidium permanganate leads to the formation of rubidium manganate intermediates. It breaks down into manganese dioxide, rubidium oxide and oxygen. The decomposition temperature is between 200 and 300 °C.{{citation|author=Z. Gontarz, B. Pisarska|date=September 1990|doi=10.1007/BF01914135|issue=6|pages=2113–2117|periodical=Journal of Thermal Analysis and Calorimetry|title=Thermal decomposition stages of potassium, rubidium and caesium permanganates|volume=36|s2cid=95763664 }} Drift-away oxygen caused an 8% mass loss in the product.
:{{chem2| 10RbMnO4 -> 3Rb2MnO4 + 7MnO2 + 2Rb2O + 6O2 ↑ }}
:{{chem2| 2Rb2MnO4 -> 2MnO2 + 2Rb2O + O2 ↑ }}
Total reaction:
:{{chem2| 4RbMnO4 -> 4MnO2 + 2Rb2O + 3O2 ↑ }}
Uses
In qualitative analysis, rubidium permanganate is used as a reagent to detect perchlorate ions. It is produced as an intermediate from rubidium nitrate and potassium permanganate and precipitates with existing perchlorate ions as RbClO4·RbMnO4 mixed crystal.{{citation|author=E. Gerdes|date=2001|edition=2|isbn=978-3-540-67875-5|pages=139|publisher=Springer|title=Qualitative anorganische Analyse|type=Ein Begleiter für Theorie und Praxis|url={{Google books|fQddWoAP7mEC||page=139|plainurl=yes}}}}
References
{{reflist}}
{{Rubidium compounds}}
{{Permanganates}}