Balance the chemical equation given below,and determine the number of grams of MgO needed to produce 15.0 g of Fe₂O₃.
_____ MgO(s) + _____ Fe(s) → _____ Fe₂O₃(s) + _____ Mg(s)

Question

Balance the chemical equation given below,and determine the number of grams of MgO needed to produce 15.0 g of Fe₂O₃. _____ MgO(s)+ _____ Fe(s)→ _____ Fe₂O₃(s)+ _____ Mg(s)

Quizplus · Accepted Answer

The balanced equation is 3MgO + 2Fe → Fe2O3 + 3Mg. The molar mass of Fe2O3 is 159.7 g/mol, and the molar mass of MgO is 40.3 g/mol. To produce 15.0 g of Fe2O3, you need (15.0 g / 159.7 g/mol) = 0.0939 mol of Fe2O3. From the balanced equation, 3 moles of MgO are needed for 1 mole of Fe2O3, so you need 0.0939 mol × 3 = 0.2817 mol of MgO. Therefore, you need 0.2817 mol × 40.3 g/mol = 11.4 g of MgO.

Balance the Chemical Equation Given Below,and Determine the Number of Grams