Manganese dioxide dehydration

Alternatively, manganese dioxide is heated strongly with dehydrated iron(II)... 

Zn(OH)2 is soluble in the alkaline solution as [Zn(OH)3]- until the solution is saturated with K[Zn(OH)3]. In addition Zn(OH)2 can be dehydrated to ZnO. An enhanced power density (when compared with the - Leclanche cell) is accomplished by using particulate zinc (flakes) soaked with the alkaline electrolyte solution. This anode cannot be used as a cell vessel like in the Leclanche cell. Instead it is mounted in the core of the cell surrounded by the separator the manganese dioxide cathode is pressed on the inside of the nickel-plated steel can used as battery container. In order to limit self-discharge by corrosion of zinc in early cells mercury was added, which coated the zinc effectively and suppressed hydrogen evolution because of the extremely low exchange current density... 

Oxalic acid is readily oxidized in watery solution it is converted into CO, and H.p, slowly by simple exposure to air, more rapidly in the presence of platinum black or of the salts of platinum and gold under the influence of sunlight or when heated with UNO, manganese dioxide, chromic acid, Br, Cl or hypochlorous acid. Its oxidation, when it is triturated dry with pure oxide of lead is suflUciently active to heat the mass to redness. H,SO, ILPO, and other dehydrating agents decompose it into H,0, 00, and C(l,. 

A magnetic study of dehydration in manganese dioxide gel has been made in the writer s laboratory. This is parallel to that described above for chromia gel. As in Table III, the dehydration indicated was cumulative. The expected loss of oxygen occurred after long dehydration. The analytical results are, therefore, more conveniently expressed in terms of a formula. (See Table IV.)... 

CrOs-pyridine-methylene chloride. The oxidation of 3a,5a-cyclocholest-7-ene-6-ol (1) to the ketone (2) is unsatisfactory with either manganese dioxide (no reaction below 40°) or CrOs in pyridine (dehydration to the A > >-dicne). 

The subsequent dehydration of ethers 13, 14, 20 and 21 was carried out by means of manganese dioxide in boiling acid. The hydrolysis of obtained esters 15,... 

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