Ammonium permanganate

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Ammonium permanganate
Ammonium permanganate.png
Identifiers
CAS number 13446-10-1 N
ChemSpider 55512 YesY
KEGG D02053 N
Jmol-3D images {{#if:O- [Mn](=O)(=O)=O.N+[O-][Mn](=O)(=O)=O.[NH4+]|Image 1
Image 2
Properties
Molecular formula 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 °C decomp.
Solubility in water 8.0 g/100 ml at 15 °C
Structure
Crystal structure Orthorhombic
Thermochemistry
Std molar
entropy
So298
J.K−1.mol−1
Std enthalpy of
formation
ΔfHo298
kJ.mol−1
Hazards
MSDS [ External MSDS]
Main hazards Oxidant (O), Harmful (Xn), Dangerous for the environment (N)
NFPA 704
Flammability code 0: Will not burn. E.g., water Health code 0: Exposure under fire conditions would offer no hazard beyond that of ordinary combustible material. E.g., sodium chloride Reactivity code 3: Capable of detonation or explosive decomposition but requires a strong initiating source, must be heated under confinement before initiation, reacts explosively with water, or will detonate if severely shocked. E.g., fluorine Special hazard OX: Oxidizer. E.g., potassium perchlorateNFPA 704 four-colored diamond
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 noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 N (verify) (what is: YesY/N?)
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][unreliable source?]

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. ^ "Manganese". Classic Encyclopedia. 1911. 
  3. ^ Seymour M. Kaye (1978). Encyclopedia of Explosives and Related Items 8. 
  4. ^ Org Prep Daily (March 16, 2008). "Tetrabutylammonium Permanganate".