C-06-Q131mediumsingle_mcqIn 2Mg+O2→2MgO\mathrm{2Mg + O_2 \to 2MgO}2Mg+O2→2MgO, O2\mathrm{O_2}O2 needed for 5 g Mg is approximately—a2 gb3.33 gc5 gd8 g