Calcium permanganate is an oxidizing agent and chemical compound with the chemical formula Ca(MnO4)2. It consists of the metal calcium and two permanganate ions. It is noncombustible, but, being a strong oxidizing agent, it will accelerate the burning of combustible material. If the combustible material is finely divided, the resulting mixture may be explosive. Contact with liquid combustible materials may result in spontaneous ignition. Contact with sulfuric acid may cause fires or explosions. Mixtures with acetic acid or acetic anhydride can explode if not kept cold. Explosions can occur when mixtures of calcium permanganate and sulfuric acid come into contact with benzene, carbon disulfide, diethyl ether, ethyl alcohol, petroleum, or other organic matter.
3D model (JSmol)
|Molar mass||277.9493 g/mol|
|Appearance||purple crystals |
|Melting point||140 °C (284 °F; 413 K) (decomposes, tetrahydrate)|
331 g/100 mL (14 °C)
338 g/100 mL (25 °C)
|Solubility||soluble in ammonium hydroxide |
decomposes in alcohol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
It is prepared from the reaction of potassium permanganate with calcium chloride or from the reaction of aluminium permanganate with calcium oxide. It can be also prepared by reacting manganese dioxide with a solution of calcium hypochlorite and a little bit of calcium hydroxide to increase the pH level. If manganese dioxide is heated with calcium hydroxide with an oxidier such as Ca(NO3)2, Ca(ClO3)2, or Ca(ClO4)2, it will produce calcium manganate or mangamite ('hypomanganate').