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Properties of Potassium permanganate (KMnO 4 ) 1. Potassium permanganate (KMnO 4 ): Action of Heat Potassium permangante on strong heating gives potassium manganate, manganese dioxide and oxygen. 2 KMnO 4 ----------> K 2 MnO 4 + MnO 2 + O 2 2. Oxidising properties of Potassium permanganate (KMnO 4 ) Potassium permanganate is a powerful oxidizing agent in alkaline or acidic solution. The relevant half reactions are: 1. Alkaline medium (pH > 7) MnO 4 - + 2H 2 O + 3 e - ----------> MnO 2 + 4OH - 2. Acidic medium (pH <7) MnO 4 - + 8H + + 5e - ----------> Mn 2+ + 4H 2 O A few important oxidizing reactions of Potassium permanganate ( KMnO 4 ) 1. In acidic medium potassium permanganate oxidizes green ferrous salts to yellow ferric salts MnO 4 - + 8H + + 5Fe 2+ ----------> 5Fe 3+ + Mn 2+ + 4H 2 O 2. in acidic medium potassium permanganate oxidizes oxalic acid or oxalate salts to CO 2 and water 2 MnO 4 - + 16H + + 5 C 2 O ...

Pottassium Permanganate ( KMnO 4 ) is prepared from Pyrolusite ore ( MnO 2 ). The finely powdered Pyrolusite ore ( MnO 2 ) is fused with an alkali metal hydroxide like KOH in the presence of air or an oxidizing agent like KNO 3 to give the dark green potassium Manganate ( K 2 MnO 4 ). Potassium manganate disproportionate in a neutral or acidic solution to give potassium permanganate . 2 MnO 2 + 4 KOH + O 2 ----------> 2K 2 MnO 4 + 2H 2 O 3 MnO 4 2- + 4H + ------------> 2MnO 4 - + MnO 2 + 2H 2 O Commercially potassium permanganate is prepared by the alkaline oxidative fusion of Pyrolusite ore ( MnO 2 ) followed by the electrolytic oxidation of manganate (4) ion . 2 MnO 2 + 4KOH + O 2 -----------> 2 K 2 MnO 4 + 2H 2 O MnO 4 2- ------( electrolytic oxidation )----> MnO 4 - + e - Properties Potassium permanganate forms dark purple (almost black) crystals , which are iso structural with those of KCLO 4 . It has weak temperature dependent...