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Naddika [18.5K]
3 years ago
14

How much energy is evolved during the formation of 98.7 g of Fe, according to the reaction below? Fe2O3(s) + 2 Al(s) → Al2O3(s)

+ 2 Fe(s) ΔH°rxn = -852 kJ How much energy is evolved during the formation of 98.7 g of Fe, according to the reaction below? Fe2O3(s) + 2 Al(s) → Al2O3(s) + 2 Fe(s) ΔH°rxn = -852 kJ 753 kJ 482 kJ 1.51 x 103 kJ 4.20 x 103 kJ 241 kJ
Chemistry
1 answer:
gtnhenbr [62]3 years ago
6 0

Answer:

-753kJ of energy are involved

Explanation:

Based on the reaction:

Fe₂O₃(s) + 2 Al(s) → Al₂O₃(s) + 2 Fe(s) ΔH°rxn = -852 kJ

<em>When 2 moles of Fe are produced, there are released -852kJ.</em>

<em />

98.7g of Fe are:

98.7g Fe × (1mol / 55.845g) = 1.767 moles of Fe

If 2 moles of Fe are producen when -852 kJ of energy are involved, 1.767 moles of Fe envolved:

1.767mol × (-852kJ / 2mol Fe) = <em>-753kJ of energy are involved</em>

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