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It is a purplish-black crystalline salt, which dissolves in water as K + and MnO − 4 ions to give an intensely pink to purple solution. Potassium permanganate is widely used in the chemical industry and laboratories as a strong oxidizing agent , and also as a medication for dermatitis , for cleaning wounds , and general disinfection .
Heterogeneous OER is sensitive to the surface which the reaction takes place and is also affected by the pH of the solution. The general mechanism for acidic and alkaline solutions is shown below. Under acidic conditions water binds to the surface with the irreversible removal of one electron and one proton to form a platinum hydroxide. [4]
The white smoke-like vapor produced by the reaction is a mixture of carbon dioxide gas and water vapor. Since the reaction is highly exothermic, initial sparking occurs, followed by a lilac- or pink-colored flame. [9] When energy or heat is added to electrons, their energy level increases to an excited state.
In an acidic solution, permanganate(VII) is reduced to the pale pink manganese(II) (Mn 2+) with an oxidation state of +2. 8 H + + MnO − 4 + 5 e − → Mn 2+ + 4 H 2 O. In a strongly basic or alkaline solution, permanganate(VII) is reduced to the green manganate ion, MnO 2− 4 with an oxidation state of +6. MnO − 4 + e − → MnO 2− 4
Chemical chameleon reaction. The chemical chameleon is a redox reaction, well known from classroom demonstrations, that exploits the dramatic color changes associated with the various oxidation states of manganese.
The contaminants are determined to be mostly ash and water. Toxic gases such as dinitrogen tetraoxide and nitrogen dioxide are evolved in the process. The final product is typically 47.06% carbon, 27.97% oxygen, 22.99% water, and 1.98% ash with a carbon-to-oxygen ratio of 2.25. All of these results are comparable to the methods that preceded them.
A homogeneous WOC [Co(Py 5)(H 2 O)](ClO 4) 2 [10] operates by a proton-coupled electron transfer to form a [Co III--OH] 2+ species, which on further oxidation forms a Co IV intermediate. The intermediate formed reacts with water to liberate O 2. The cobalt-polyoxometalate complex [Co 4 (H 2 O) 2 (α-PW 9 O 34) 2] 10− is highly efficient WOC. [11]
Ammonium permanganate decomposes explosively to manganese dioxide, nitrogen, and water: [2] 2 NH 4 MnO 4 → 2 MnO 2 + N 2 + 4 H 2 O. Ammonium permanganate decomposes slowly in storage even at normal temperatures. A sample stored for 3 months was only 96% pure, after 6 months it assumed color of iodine and had strong smell of nitrogen oxides.