In the equation __Mg + O₂ → __MgO, what is the correct balancing number in front of MgO?
Answer and explanation
Correct answer: C. 2
- Step 1: There are two oxygen atoms on the left, so two MgO are needed.
- Step 2: Then two Mg are needed: 2Mg + O₂ → 2MgO.
Answer
2.
Why not the others: 1: the equation would not balance. 3: the equation would not balance. 4: the equation would not balance.
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