What is the oxidation number of Mn in KMnO4?
Answer and explanation
Correct answer: D. +7
- Step 1: The oxidation numbers in a neutral compound add up to zero, with O = -2 and H or K = +1.
- Step 2: Solving for Mn gives +7.
Answer
+7.
Why not the others: '+5' miscounts the oxygen contribution; '+8' adds one to the correct oxidation number; '-7' uses the wrong sign.
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