AP Chemistrymediummcq1 pt
In the reaction Fe₂O₃ + 3CO → 2Fe + 3CO₂, what is the oxidation number change for iron?
A.+3 to 0
B.0 to +3
C.+2 to +3
D.+3 to +2
Explanation
Core Concept
Iron in Fe₂O₃ is +3 (each O −2); in Fe metal it is 0. Iron gains three electrons per atom — reduction.
Correct Answer
A+3 to 0
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