Determine the Standard Enthalpy of Formation of Fe₂O₃(s)given the Thermochemical

question 25

Multiple Choice

Determine the standard enthalpy of formation of Fe₂O₃(s) given the thermochemical equations below. Fe(s) + 3 H₂O( ) → Fe(OH) ₃(s) + 3/2 H₂(g)
Δ_rH° = +160.9 kJ/mol-rxn
H₂(g) + 1/2 O₂(g) → H₂O( )
Δ_rH° = -285.8 kJ/mol-rxn
Fe₂O₃(s) + 3 H₂O( ) → 2 Fe(OH) ₃(s)
Δ_rH° = +288.6 kJ/mol-rxn

• A) -252.6 kJ/mol-rxn
• B) +163.7 kJ/mol-rxn
• C) -824.2 kJ/mol-rxn
• D) +33.2 kJ/mol-rxn
• E) + 890.6 kJ/mol-rxn

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