Manganese heptoxide

Manganese Heptoxide. Mn2 07, mw 221.87, brown liq, mp 5.9°, bp defl 55°, explds 95°, d 2.396g/cc v sol in cold w, decomposes in hot w, sol in sulfuric acid. Prepd by adding powd K permanganate in small quant to cooled coned sulfuric acid. A dark green soln is formed which is liable to expld violently in contact... 

The moist salt exploded during drying over the concentrated acid in a vacuum desiccator, (presumably owing to formation of traces of manganese heptoxide from reaction with sulfuric acid vapour). 

In a demonstration of the powerful oxidant effect of manganese heptoxide on ethanol layered on top of sulfuric acid, it is essential to observe all the precautions given to prevent violent exothermic reactions. 

Manganese halides, 15 573-574 Manganese heptoxide, 15 597 Manganese hydroxide, 15 575 Manganese(II) ion, complexes containing, 15 573... 

Due to its different oxidation states, manganese can form a number of different compounds with oxygen for instance, manganese monoxide(II) (MnO), manganese sesquinoxide(III) (Mn Oj), manganese dioxide(IV) (MnO ), and manganese heptoxide(VII) (Mn O ). 

Manganese heptoxide, Mn20 , which explodes at 70°C, can form in KMnO /HgSC mixtures. 

Permangank acid, HMn04, is a strong acid which is very unstable. Its anhydride, manganese heptoxide, can be made by the reaction of potassium permanganate and concentrated sulfuric acid ... 

Reagents that contain manganese heptoxide and perchloric acid and also solutions of sodium azide and iodine azide should never be sprayed, as these can cause explosions in the air extraction ducting. 

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