Red oxide of manganese

Synonyms trimanganese tetraoxide manganomanganic oxide red oxide of manganese... 

All the higher oxides of manganese arts reduced to the condition of protccompounds by the action of warm sulphuric or hydrochloric acid, with the elimination of oxygen or chlorine, as the case may he. The following equations represent the action of hydroohloric acid upon the binoxide, the sesquioxida, and the red oxide of manganese —... 

WTien this oxide, or the peroxide of cobalt, are heated in the air, they both yield a black oxide, which corresponds to the red oxide of manganese, its formula being Co, 0 = CoO - - C,0. The green hydrate, formed when hydrate of the protoxide is exposed to the air, is a hydrate of this oxide. 

Sodium bismuthate (oxidation of manganese) heat 20 parts of NaOH nearly to redness in an iron or nickel crucible, and add slowly 10 parts of basic bismuth nitrate which has been previously dried. Add 2 parts of sodium peroxide, and pour the brownish-yellow fused mass on an iron plate to cool. When cold break up in a mortar, extract with water, and collect on an asbestos filter. 

Klaproth s first analysis of lepidolite did not show the presence of any alkali. When he examined it a second time, however, he wrote Since the analysis of leucite, described in the earlier part of this work, has evidently proved that it contains the vegetable alkali as one of its essential constituent parts, it was to be expected that this alkaline substance might likewise be found in the mixture of various other species of stones and earths. The first confirmation of this conjecture has been afforded to me by the Lepidolite. His final analysis of "the amethystine red lepidolite yielded silica 54.50, alumina 38.25, potash 4, oxides of manganese and iron 0.75, and loss, partly consisting of water 2.50 per cent (71). Klaproth s analysis failed to show the presence of two essential constituents of lepidolite lithium (which had not yet been discovered) and fluorine. 

This may be identified (a) by its odour (cautiously smell the vapour after removing the test-tube or small beaker from the flame) (b) by the formation of white fumes of ammonium chloride when a glass rod moistened with concentrated hydrochloric acid is held in the vapour (c) by its turning moistened red litmus paper blue or turmeric paper brown (d) by its ability to turn filter paper moistened with mercury(I) nitrate solution black (this is a very trustworthy test ) and (e) filter paper moistened with a solution of manganese(II) chloride and hydrogen peroxide gives a brown colour, due to the oxidation of manganese by the alkaline solution thus formed. 

Dissolve 16 parts gum-arabic in the least possible quantity of water, and mix with it 9 parts phosphorus iu powder (see No. 4338) then add 14 parts nitre (saltpetre), and 16 parts of either vermilion (red sulphuret of mercury), or binoxide (black oxide) of manganese, aud form the whole into a paste. Dip the matches into this pasto, and then let them dry. When quite dry they are to be dipped into a very dilute copal or lac varnish, and again dried by this means they are less likely to suffer from damp weather. 

The black oxide of manganese is heated to redness in an iron or clay retort (Scheele, 1775) and 100 grama yield 8.51 litres of oxygen. 

Or Mix 28 parts of perfectly diy ferro-cyonide of potassium with 14 paits of black oxide of manganese, both pure and in fine powder then place them on a smooth iron plate, and heat them to a doll red, over a... 

This oxide is obtained when the peroxide is acted on by hydrogen gas at a red-heat. But the best method is to heat to redness a mixture of 1 part of dry chloride of manganese, 1 part of sal-ammoniac, and 2 parts of diy carbonate of soda. The chloride acts on the soda, MnCl + NaO = MnO -b NaCl forming oxide of manganese and chloride of sodium while the carbonic acid escapes as gas the sal-ammoniac is also expelled ... 

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