How much energy is evolved during the formation of 197 g of Fe,according to the reaction below?
Fe₂O₃(s) + 2 Al(s) → Al₂O₃(s) + 2 Fe(s) ΔH°_rxn= -852 kJ

Question

How much energy is evolved during the formation of 197 g of Fe,according to the reaction below? Fe₂O₃(s)+ 2 Al(s)→ Al₂O₃(s)+ 2 Fe(s)ΔH°_rxn= -852 kJ

Quizplus · Accepted Answer

The molar mass of Fe is 55.85 g/mol. For 197 g of Fe, the moles of Fe are 197 g / 55.85 g/mol = 3.53 mol. The reaction produces 2 moles of Fe per reaction, so 3.53 mol of Fe corresponds to 3.53 / 2 = 1.765 reactions. The energy evolved is 1.765 reactions × (-852 kJ/reaction) = -1504.38 kJ, which is approximately 1.52 × 10³ kJ.

How Much Energy Is Evolved During the Formation of 197