Balanced chemical equation for ' Mg + O_{2  -->} MgO '

Dear student
Magnesium reacts with oxygen to form its oxide. 
since, oxygen is found in nature as a bimolecular species, hence the equation would be
$$\begin{gathered} Mg + O_2\to MgO \\ balanced equation : \\ 2Mg + O_2\to 2 MgO \end{gathered}$$

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