Magnesium oxide is a compound so the terms metal and nonmetal do not properly apply to it.
because it has an oxygen on it. Mg + O > MgO (That's the unbalanced formula)
No, magnesium is its natural state while magnesium oxide is formed magnesium heated in oxygen or air
Oxygen.
2Mg + O2 --> MgO Oxygen oxidizes the Mg to Mg2+, which in turn reacts with oxygen to form MgO
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