Ammonium permanganate

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Ammonium permanganate
Ammonium permanganate.png
Names
IUPAC name
Ammonium manganate(VII)
Other names
Ammonium permanganate
Identifiers
3D model (JSmol)
ChemSpider
UN number 3085, 1482
Properties
NH4MnO4
Molar mass 136.974 g/mol
Appearance rhombic needle crystals or powder with rich violet-brown or dark purple metallic sheen, become steel-gray in storage;
magenta–rose in solution
Density g/cm3, solid
Melting point decomposes
8.0 g/100 ml at 15 °C
Structure
Orthorhombic
Thermochemistry
J.K−1.mol−1
kJ.mol−1
Hazards
Main hazards Oxidant (O), Harmful (Xn), Dangerous for the environment (N)
Safety data sheet [ External MSDS]
NFPA 704
Related compounds
Other anions
Ammonium perrhenate
Other cations
Sodium permanganate; Potassium permanganate
Related compounds
Potassium manganate (K2MnO4); Manganese heptoxide;

Sodium permanganate; Potassium permanganate

Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Ammonium permanganate is the chemical compound NH4MnO4, or NH3·HMnO4. It is soluble in water. It is a strong oxidizer, owing to its permanganate anion, and it is a moderately strong explosive, owing to the combination of oxidizer permanganate anion and reducing ammonium cation. Dry ammonium permanganate can detonate by heat, shock, or friction, and it may explode at temperatures above 140 °F (60 °C).[1]

Ammonium permanganate decomposes explosively to manganese dioxide, nitrogen, and water:[2]

2 NH4MnO4 → 2 MnO2 + N2 + 4 H2O

Ammonium permanganate was first prepared by Eilhard Mitscherlich in 1824 by reaction of silver permanganate with equal molar amount of ammonium chloride, filtering the silver chloride and evaporating the water. It can be also prepared in a similar way from barium permanganate and ammonium sulfate.

Ammonium permanganate decomposes slowly in storage even at normal temperatures. A sample stored for 3 months was only 96% pure, after 6 months it assumed color of iodine and had strong smell of nitrogen oxides. It emits toxic fumes when decomposed by heat.[3]

Quaternary ammonium permanganate compounds can be prepared, such as tetrabutylammonium permanganate.[4][unreliable source?]

References[edit]

  1. ^ "MSDS Chemical Information File: Ammonium Permanganate". February 1988.
  2. ^ Wikisource Chisholm, Hugh, ed. (1911). "Manganese". Encyclopædia Britannica. 17 (11th ed.). Cambridge University Press. pp. 569–571.
  3. ^ Seymour M. Kaye (1978). Encyclopedia of Explosives and Related Items. 8.
  4. ^ Org Prep Daily (March 16, 2008). "Tetrabutylammonium Permanganate".