Answer: 0.385 moles
Explanation:-
Combustion is a type of chemical reaction in which a substance is reacted with oxygen.
The balanced chemical reaction between magnesium and oxygen is:
[tex]2Mg+O_2 \rightarrow 2MgO[/tex]
From the stoichiometry:
2 moles of magnesium react with = 1 mole of oxygen
Thus 0.770 moles of magnesium react with = [tex]\frac{1 }{2}\times 0.770=0.385[/tex] moles of oxygen
Thus 0.385 moles of [tex]O_2[/tex] are consumed when 0.770 mol of magnesium burns in excess oxygen.
