How many grams of MgC03 contain 24-00 g of oxygen? (The molar mass of MgC03 is 84-30 g mol-1)

To find the mass of magnesium carbonate (MgCO3) containing 24.00 g of oxygen, we first determine the mass of oxygen in one mole of the compound. MgCO3 contains three oxygen atoms. Given the atomic mass of oxygen is approximately 16.00 g/mol, one mole of MgCO3 contains 48.00 g of oxygen (3 × 16.00 g/mol). The molar mass of MgCO3 is provided as 84.30 g/mol. Using stoichiometry, if 84.30 g of MgCO3 contains 48.00 g of oxygen, then 24.00 g of oxygen (which is exactly half of 48.00 g) will be present in half a mole of the compound. Calculating this gives: (24.00 g / 48.00 g) × 84.30 g = 42.15 g. Therefore, 42.15 g of MgCO3 contains 24.00 g of oxygen.