How much energy is evolved during the formation of 816 g of Al₂O₃,according to the reaction below? Fe₂O₃(s)+ 2 Al(s)→ Al₂O₃(s)+ 2 Fe(s)ΔH°_rxn= -852 kJ A) 6.82 × 10³ kJ B) 9.90 × 10³ kJ C) 5.60 × 10³ kJ D) 4.50 × 10² kJ E) 6.60 × 10² kJ

Question

Quizplus · Accepted Answer

The molar mass of Al₂O₃ is approximately 102 g/mol. For 816 g of Al₂O₃, the number of moles is 816 g / 102 g/mol = 8 moles. Since the reaction releases 852 kJ per mole of Al₂O₃ formed, the total energy evolved is 8 moles × 852 kJ/mol = 6.82 × 10³ kJ.

How Much Energy Is Evolved During the Formation of 816