Manganese dioxide, also known as manganese(IV) oxide, is a chemical compound of manganese and oxygen. It contains manganese in the +4 oxidation state. Its chemical formula is MnO2. It is black and powdery. It is used as a depolarizer in alkaline batteries and Leclanche batteries. It is found naturally as the mineral pyrolusite.
Quick facts Names, Identifiers ...
Manganese dioxide
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| Names |
| IUPAC names
Manganese oxide
Manganese(IV) oxide |
Other names
Pyrolusite, hyperoxide of manganese, black oxide of manganese, manganic oxide |
| Identifiers |
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3D model (JSmol) |
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| ChEBI |
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| ChemSpider |
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| ECHA InfoCard |
100.013.821 |
| EC Number |
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| RTECS number |
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| Properties |
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MnO
2 |
| Molar mass |
86.9368 g/mol |
| Appearance |
Brown-black solid |
| Density |
5.026 g/cm3 |
| Melting point |
535 °C (995 °F; 808 K) (decomposes) |
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insoluble |
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+2280.0·10−6 cm3/mol |
| Thermochemistry |
Std enthalpy of
formation ΔfHo298 |
−520 kJ·mol−1[1] |
Standard molar
entropy So298 |
53 J·mol−1·K−1[1] |
| Hazards |
| EU classification |
Harmful (Xn)
Oxidizer (O) |
| NFPA 704 |
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| R-phrases |
R20/22 |
| S-phrases |
(S2), S25 |
| Related compounds |
| Other anions |
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| Other cations |
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Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). |
| N verify (what is YN ?) |
| Infobox references |
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