Search results
Results from the WOW.Com Content Network
In a classical laboratory demonstration, heating a mixture of potassium chlorate and manganese dioxide produces oxygen gas. Manganese dioxide also catalyses the decomposition of hydrogen peroxide to oxygen and water: 2 H 2 O 2 → 2 H 2 O + O 2. Manganese dioxide decomposes above about 530 °C to manganese(III) oxide and oxygen.
Manganese oxide is any of a variety of manganese oxides and hydroxides. [1] These include Manganese(II) oxide, MnO; Manganese(II,III) oxide, Mn 3 O 4; Manganese(III) oxide, Mn 2 O 3; Manganese dioxide, MnO 2; Manganese(VI) oxide, MnO 3; Manganese(VII) oxide, Mn 2 O 7; Other manganese oxides include Mn 5 O 8, Mn 7 O 12 and Mn 7 O 13.
An alternative route, mostly for demonstration purposes, is the oxalate method, which also applicable to the synthesis of ferrous oxide and stannous oxide. Upon heating in an oxygen-free atmosphere (usually CO 2), manganese(II) oxalate decomposes into MnO: [9] MnC 2 O 4 ·2H 2 O → MnO + CO 2 + CO + 2 H 2 O
Manganese(II,III) oxide is the chemical compound with formula Mn 3 O 4. Manganese is present in two oxidation states +2 and +3 and the formula is sometimes written as MnO · Mn 2 O 3 . Mn 3 O 4 is found in nature as the mineral hausmannite .
Manganese(III) oxide is formed by the redox reaction in an alkaline cell: 2 MnO 2 + Zn → Mn 2 O 3 + ZnO [citation needed] Manganese(III) oxide Mn 2 O 3 must not be confused with MnOOH manganese(III) oxyhydroxide. Contrary to Mn 2 O 3, MnOOH is a compound that decomposes at about 300 °C to form MnO 2.
Manganese(IV) oxide was used in the original type of dry cell battery as an electron acceptor from zinc, and is the blackish material in carbon–zinc type flashlight cells. The manganese dioxide is reduced to the manganese oxide-hydroxide MnO(OH) during discharging, preventing the formation of hydrogen at the anode of the battery. [82]
The chemical reaction, in which ethylene (C 2 H 4) is oxidised by potassium permanganate (KMnO 4) to carbon dioxide (CO 2), manganese oxide (MnO 2) and potassium hydroxide (KOH), in the presence of water, is presented as follows: [55] 3 C 2 H 4 + 12 KMnO 4 + 2 H 2 O → 6 CO 2 + 2 H 2 O + 12 MnO 2 + 12 KOH
Pyrolusite is a mineral consisting essentially of manganese dioxide (Mn O 2) and is important as an ore of manganese. [7] It is a black, amorphous appearing mineral, often with a granular, fibrous, or columnar structure, sometimes forming reniform crusts. It has a metallic luster, a black or bluish-black streak, and readily soils the fingers.