In the thermite reaction 2Al(s)+FeX2OX3(s)⟶2Fe(l)+AlX2OX3(s)
what is the maximum temperature attainable by the products? Assume reactants at 25 ∘C and 1 atm and that all heat capacities remain constant.
I started by using Hess's law to find the enthalpy change of the reaction. I couldn't find a heat of formation for liquid iron so I assume I have to find that out. I just wrote out the equation Fe(s)+heat+enthalpy of fusion⟶Fe(s)
and figured the heat of formation for liquid iron at 25 ∘C is around −302.71 kJ/mol.
To find the max temperature I used ΔHr=ΔT⋅Cp(products)
and came out with an equation like −14445 kJ/mol=0.147 kJ/(mol K)⋅Tmax
This gives me a negative temperature, so I assume it is wrong. Even if I were to take the absolute value, the answer seems awfully high. I was expecting something around a few thousand degrees not near ten thousand.
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