manganese dioxide

manganese dioxide
: a dark brown or gray-black insoluble compound MnO2 found in nature as pyrolusite, made synthetically (as by decomposition of manganous nitrate or by chemical or electrolytic precipitation), and used chiefly as an oxidizing agent and a depolarizer in dry cells, in glassmaking and ceramics, as a pigment, and as a starting material for other manganese compounds (as permanganates and driers for varnishes and paints)

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manganese dioxide,
a black crystal, or brownish-black powder, used especially in making dyes, paints, and dry-cell batteries, as an oxidizing agent. Formula: MnO2

Useful english dictionary. 2012.