Answer:
769 kJ
Explanation:
We know that we will need the balanced equation with masses, molar masses, and enthalpies, so let’s gather all the information in one place.
A_r: 26.98
Fe₂O₃ + 2Al ⟶ Al₂O₃ + 2Fe; ΔH_rxn = -852 kJ
Mass/g: 48.7
1. Calculate the moles of Al
Moles of Al = 48.7 × 1/26.98
Moles of Al = 1.805 mol Al
2. Calculate the energy released
The conversion factor is 852 kJ/2 mol Al
Heat = 1.805 × 852/2
Heat = 769 kJ
