Pyrolusite properties

L. magnes, magnet, from magnetic properties of pyrolusite It. manganese, corrupt form of magnesia)... 

Explosive Properties. N trifluoride is the most stable of the N halides, but it can detonate in the presence of hydrazoic acid (Ref 13) or org compds (Ref 10). Ozone, which is one by-prod of the electrolysis of Amm bifluoride, was found by Ruff and coworkeis to cause violent expins in the reaction vessels and gas lines. They found that the ozone could be removed by passing the off-gas thru pyrolusite, thus reducing considerably the expin hazard (Ref 1). It also decomps explosively above 100° (Ref 2)... 

Manganese - the atomic number is 25 and the chemical symbol is Mn. The name derives from the Latin magnes for magnet since pyrolusite (Mn02) has magnetic properties. It was discovered by the Swedish pharmacist and chemist Carl-Wilhelm Scheele in 1774. Also in 1774, the Swedish chemist Johan Gottlieb Gahn first isolated the metal. 

It is therefore to the vital air [oxygen] of the manganese [pyrolusite], which combines with the marine acid, that the formation of the dephlogisticated marine acid is due. I ought to state that this theory was presented and announced some time ago by M. Lavoisier, and that M. de Fourcroy made use of it in his Elements of Chemistry and Natural History to explain the properties of dephlogisticated marine acid such as they were then known. 

J.22. J4.1.5 MnO2 from Fisher Properties of the following specimens from Fisher have been reported. Pyrolusite BET specific surface area 0.048 rn Vg [1703], Analytical grade TEM image available, specific surface area 0.6 mVg [908]. 

Properties Pyrolusite, stoichiometric proportion of oxygen [1709], specihc surface area 3 m /g [1709], BET specihc surface area 0.15 m7g [332,1417]. 

G. Scheele was the third chemist who tried to separate a new element from this mineral. In 1774 he submitted his paper On Manganese and Its Properties to the Stockholm Academy of Sciences in it he summed up the three years of studies of pyrolusite. In this extremely informative paper he reported the discovery of two metals (barium and manganese) and described two gaseous elements (later identified as chlorine and oxygen). Scheele established that manganese oxide differed from all earths known at the time. 

Manganese [7439-96-5], chemical symbol Mn, atomic number 24, and relative atomic mass 54.938049(9), is the first element of group VIIB(7) of Mendeleev s periodic chart. Its name is derived from the Latin word magnes, owing to the magnetic properties of pyrolusite... 

Table 8.5 Technical properties of BIRM, manganese greensand. Greensand Plus cuid Pyrolusite.

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