The first step is to convert the 55 kg of Fe₃O₄ to moles by using the molar mass, that is, 231.55 g/mol (55 kg = 55000 gms),
55000 gms × 1 mole / 231.55 gms = 237.53 moles of Fe₃O₄
For the decomposition of every 1 mole of Fe₃O₄, +1118 kJ of energy is needed. Therefore, the energy needed to decompose 237.53 moles will be:
237.53 moles of Fe₃O₄ × 1118 kJ / 1 mole = 265558 kJ
Thus, there is a need of 265558 kJ of energy to decompose 55 kg of Fe₃O₄.
