Verified answer

mass of MgO = (mass of Mg) ÷ (Molar mass of Mg) x (2 moles of MgO / 2 moles of Mg) x (Molar mass of MgO)

mass of MgO = (48 g) ÷ (24.305 g/mol) x (2/2) x (40.3044 g/mol)

mass of MgO = 79.6 g

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