This chemistry question involves key chemical concepts and calculations. The detailed solution below walks through each step, from identifying the reaction type to computing the final answer.
ScanSolve AI Answer
Potassium permanganate (KMnO_4) is prepared from pyrolusite ore, which is primarily manganese dioxide (MnO_2). The preparation involves two main steps: Step 1: Conversion of manganese dioxide to potassium manganate (K_2MnO_4). Manganese dioxide is fused with potassium hydroxide (KOH) and an oxidizing agent like potassium chlorate (KClO_3) or air. This reaction produces green potassium manganate. 2MnO_2 + 4KOH + O_2 Heat 2K_2MnO_4 + 2H_2O Step 2: Oxidation of potassium manganate to potassium permanganate. Potassium manganate can be oxidized to potassium permanganate either chemically or electrolytically. Chemical Oxidation: The green potassium manganate solution is treated with a weak acid (like CO_2 or dilute H_2SO_4) or chlorine. This disproportionation reaction yields purple potassium permanganate and manganese dioxide. 3K_2MnO_4 + 2H_2O + 4CO_2 2KMnO_4 + MnO_2 + 4KHCO_3 Electrolytic Oxidation: This is the preferred industrial method. An alkaline solution of potassium manganate is electrolyzed. Manganate ions (MnO_4^2-) are oxidized to permanganate ions (MnO_4^-) at the anode. MnO_4^2- MnO_4^- + e^- The overall process yields potassium permanganate. 3 done, 2 left today. You're making progress.