Manganese heptoxide
Template:Short description Template:Chembox
Manganese(VII) oxide (manganese heptoxide) is an inorganic compound with the formula Template:Chem2. Manganese heptoxide is a volatile liquid with an oily consistency. It is a highly reactive and powerful oxidizer that reacts explosively with nearly any organic compound. It was first described in 1860.[1] It is the acid anhydride of permanganic acid.
Properties
The crystalline form of this chemical compound is dark green. The liquid is green by reflected light and red by transmitted light.[2] It is soluble in carbon tetrachloride, and decomposes when in contact with water.
Structure
Its solubility properties indicate a nonpolar molecular species, which is confirmed by its structure. The molecules consist of a pair of tetrahedra that share a common vertex. The vertices are occupied by oxygen atoms and at the centers of the tetrahedra are the Mn(VII) centers. The connectivity is indicated by the formula O3Mn−O−MnO3. The terminal Mn−O distances are 1.585 Å and the bridging oxygen is 1.77 Å distant from the two Mn atoms. The Mn−O−Mn angle is 120.7°.[3]
Pyrosulfate, pyrophosphate, and dichromate adopt structures similar to that of Template:Chem2. Probably the most similar main group species is Template:Chem2. Focusing on comparisons within the transition metal series, Template:Chem2 and Template:Chem2 are structurally similar but the Tc−O−Tc angle is 180°. Solid Template:Chem2 is not molecular but consists of crosslinked Re centers with both tetrahedral and octahedral sites;[4] in the vapour phase it is molecular with a similar structure to Tc2O7.[5]
Synthesis and reactions
Template:Chem2 arises as a dark green oil by the addition of cold concentrated Template:Chem2 to solid Template:Chem2.[2] The reaction initially produces permanganic acid, Template:Chem2 (structurally, Template:Chem2), which is dehydrated by cold sulfuric acid to form its anhydride, Template:Chem2:
Template:Chem2 can react further with sulfuric acid to give the remarkable manganyl(VII) cation Template:Chem2, which is isoelectronic with Template:Chem2:
Template:Chem2 decomposes near room temperature, explosively so above Template:Convert. The explosion can be initiated by striking the sample or by its exposure to oxidizable organic compounds. The products are Template:Chem2 and Template:Chem2.[6] Ozone is also produced, giving a strong smell to the substance. The ozone can spontaneously ignite a piece of paper impregnated with an alcohol solution.Script error: No such module "Unsubst".
Manganese heptoxide reacts with hydrogen peroxide in presence of sulfuric acid, liberating oxygen and ozone:
References
External links
Template:Manganese compounds Template:Oxides
- ↑ Aschoff, H. Ann. Phys. Chem. Ser. 2 volume 111 (1860) page 217 and page 224.
- ↑ a b Script error: No such module "citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Wells A.F. (1962) Structural Inorganic Chemistry 3d edition Oxford University Press
- ↑ Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. Template:ISBN.