Water purification chemistry: Why is potassium permanganate (KMnO4) used in treating/purifying drinking water? Focus on its chemical action on microbes and organic contaminants during disinfection. Choose the correct reason.

Given data

• Reagent: Potassium permanganate (KMnO₄).
• Use case: Disinfection/oxidation in water treatment.

Concept/ApproachKMnO₄ is a strong oxidising agent. Oxidation damages microbial cell components and converts certain dissolved organics/iron/manganese to insoluble forms that can be removed.

ReasoningKMnO₄ + organics/Fe²⁺/Mn²⁺ → oxidised products + MnO₂(s).Disinfection efficacy stems from oxidation, i.e., its chemical sterilising action.

Common pitfallsConfusing its role as reducing agent (incorrect here) or thinking it merely “dissolves impurities”.

Final AnswerIt is an oxidising agent