マンガン (III) オキシド 化學(xué)特性,用途語(yǔ),生産方法
用途
情報(bào)なし
化學(xué)的特性
manganese(III) oxide is a black, lustrous powder, sometimes tinged brown. Very hard.decomposes at 1080℃. Soluble in cold hydrochloric acid; not soluble in nitric acid (decomposes), hot sulfuric acid; insoluble in water. Noncombustible.
manganese(III) oxide is obtained by igniting manganese(IV) oxide or a manganese(II) salt in air at 800°C. It reacts slowly with cold dilute acids to form manganese(III) salts. Manganese(III) oxide occurs in nature as braunite (3Mn2O3.MnSiO3 ) and the monohydrate (Mn2O 3.H2O) occurs in the mineral manganite. The manganese(III) oxide crystal lattice contains Mn3+ and O2– ions. With concentrated alkalis, it undergoes disproportionation to give manganese(II) and manganese(IV) ions.
使用
Manganese(III) oxide is used to produce ceramic magnets and semiconductors. Further, it serves as a precursor to lithium manganese oxide. In addition to this, it acts as a useful battery cathode.
製造方法
Anhydrous manganese(III) oxide is found as the mineral braunite, Mn2O3, while a hydrated form, Mn2O3.H2O, which is chemically more reactive, occurs as manganite. Manganese forms both anions and cations in oxidation state +3. Simple salts of tervalent manganese are not stable. However, complexes are more stable, the hexacyanomanganates(III) being an example: K3Mn(CN)6 is a red crystalline solid, isomorphous with potassium hexacyanoferrate(III) and slowly hydrolysed.
Manganese(III) oxide is formed as a grey solid by heating manganese(IV) oxide to 700°C for several hours:
4MnO2 ---> 2Mn203 + O2
It is converted into trimanganese tetroxide when heated above 940°C in air or reduced by hydrogen above 230°C. Hot concentrated hydrochloric acid is oxidized to chlorine by manganese(III) oxide:
Mn203 (s) + 6H + + 2e- ==2Mn2+ + 3H2O
Mn203 (s) + 6H + + 2Cl- ---> 2Mn2+ + 3H2O + Cl2
定義
In nature as manganite,
a manganese ore.
危険性
Flammable in finely divided form. Toxic by
inhalation of dust.
安全性プロファイル
Moderately toxic by
subcutaneous and intratracheal routes. See
also MANGANESE COMPOUNDS.
マンガン (III) オキシド 上流と下流の製品情報(bào)
原材料
準(zhǔn)備製品