What is the oxidation number of Mn in MnO₂?
Answer and explanation
Correct answer: C. +4
- Step 1: The oxidation numbers in a neutral compound add up to zero (H is +1, O is −2). Step 2. Solving for Mn gives +4. Answer: +4. Why not the others: +2 is what you get if you miscount the oxidation numbers of the other atoms. +7 is what you get if you miscount the oxidation numbers of the other atoms. +6 is what you get if you miscount the oxidation numbers of the other atoms.
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