Problem: The thermite reaction, in which powdered aluminum reacts with iron oxide, is highly exothermic:2Al(s) + Fe2O3(s) → Fe(s) + 2Al2O3(s)Use standard enthalpies of formation to find ΔH˚rxn for the thermite reaction.Standard Thermodynamic Quantities for Selected Substances at 25 oC Reactant or productΔH˚f(kJ/mol)Al(s)0.0Fe2O3(s)-824.2Al2O3(s)-1675.7Fe(s)0.0

FREE Expert Solution

We are asked to find ΔH˚rxn for the thermite reaction.

2Al(s) + Fe2O3(s) → Fe(s) + 2Al2O3(s)



ΔH°rxn=ΔH°f, prod-ΔH°f, react


Note that we need to multiply each ΔH˚f by the stoichiometric coefficient since ΔH˚f is in kJ/mol. 

Also, note that ΔH˚f for elements in their standard state is 0.



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Problem Details

The thermite reaction, in which powdered aluminum reacts with iron oxide, is highly exothermic:
2Al(s) + Fe2O3(s) → Fe(s) + 2Al2O3(s)

Use standard enthalpies of formation to find ΔH˚rxn for the thermite reaction.

Standard Thermodynamic Quantities for Selected Substances at 25 o

Reactant or productΔH˚f(kJ/mol)
Al(s)0.0
Fe2O3(s)-824.2
Al2O3(s)-1675.7
Fe(s)0.0


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