In determining the empirical formula of a compound, you must
convert the mass of each element to moles. Since the given mass for this
problem is 0.212 grams of Magnesium and 0.140 grams of Oxygen, just divide the
mass by the molar mass of Magnesium (24.305 g/mol) and Oxygen (16 g/mol).You’ll
get 0.00872 moles of Magnesium and 0.00875 moles of Oxygen. You then divide the
each mole value with the smallest calculated number of moles which is 0.00872.
You will get an empirical formula of MgO.
