CAS number : 1317-34-6
Molecular weight :157.87
Molecular formula/chemical symbol :Mn2O3
Description :
Keywords:Oxide
Heating MnO2 in air at below 800 °C α-Mn2O3 is produced (higher temperatures produce Mn3O4).γ-Mn2O3 can be produced by oxidation followed by dehydration of manganese(II) hydroxide. Many preparations of nano-crystalline Mn2O3 have been reported, for example syntheses involving oxidation of MnII salts or reduction of MnO2.
Manganese (III) oxide is formed by the redox reaction in an alkaline cell:
2 MnO2 + Zn → Mn2O3 + ZnO
Manganese (III) oxide Mn2O3 must not be confused with MnOOH manganese (III) oxohydroxide. Contrary to Mn2O3, MnOOH is a compound that decomposes at about 300 °C to form MnO2.
Mn2O3 is unlike many other transition metal oxides in that it does not adopt the corundum (Al2O3) structure. Two forms are generally recognized, α-Mn2O3 and γ-Mn2O3, although a high pressure form with the CaIrO3 structure has been reported too.
α-Mn2O3 has the cubic bixbyite structure, which is an example of a C-type rare earth sesquioxide (Pearson symbol cI80, space group Ia3, #206). The bixbyite structure has been found to be stabilised by the presence of small amounts of Fe3+, pure Mn2O3 has an orthorhombic structure (Pearson symbol oP24,space group Pbca, #61).
γ-Mn2O3 has a structure related to the spinel structure of Mn3O4 where the oxide ions are cubic close packed. This is similar to the relationship between γ-Fe2O3 and Fe3O4. γ-Mn2O3 is ferrimagnetic with a Neel temperature of 39 K.
Manganese(III) oxide |
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Other names[hide] dimanganese trioxide, manganese sesquioxide, manganic oxide |
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Identifiers |
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OP915000 |
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Properties |
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Mn2O3 |
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157.8743 g/mol |
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Appearance |
brown or black crystalline |
9.53 g/cm3 (alpha form) |
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888 °C (alpha form) |
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Solubility in water |
0.00504 g/100 mL (alpha form) |
insoluble in alcohol, acetone |
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Structure |
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Ia-3, No. 206 |
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Related compounds |
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Other anions |
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Other cations |
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Related compounds |
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Y (verify) (what is: Y/N?) |
USES :
Report :
Product name |
Manganese trioxide |
CAS:1317-34-6 |
Description |
Brown or black crystalline |
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TEST ITEMS |
TEST RESULTS |
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Mn |
≥70% |
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SiO2 |
≤0.005% |
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H2O |
≤0.5% |
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CaO |
≤0.001% |
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K |
≤0.001% |
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Na |
≤0.001% |
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Pb |
≤0.002% |
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P |
≤0.5% |
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S |
≤0.5% |
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Se |
≤0.005% |