Answer: KMnO 4 (potassium permanganate).
- A H<sub>2</sub> gas under typical conditions
- B C (carbon) according to standard textbooks
- C KMnO<sub>4</sub> (potassium permanganate)
- D Na (sodium metal) in general practice
Correct answer: C. KMnO<sub>4</sub> (potassium permanganate)
Explanation: KMnO₄ contains Mn in the +7 oxidation state; it readily accepts electrons (Mn goes from +7 to +2 or +4), making it a strong oxidising agent.
Electron transfer in a redox reaction: zinc loses electrons (oxidised, acts as reducing agent) and copper(II) ions gain those same electrons (reduced, acts as oxidising agent).
Concept context
Master electron transfer in chemistry: assign oxidation states, balance half-reactions, identify oxidising and reducing agents, and connect redox to everyday reactions.