Question

What is the enthalapy of a Thermite Reaction?

Answer 1

Thermite Reaction-

2 Al(s) + Fe2O3(s) --> 2Fe (s) + Al2O3 (s)

The [delta]H for this reaction is the sum of the [delta] Hfo's of the products - the sum of the [delta] Hfo's of the reactants (multiplying each by their stoichiometric coefficient in the balanced reaction equation), i.e.:

[delta]Horxn = (1 mol)( [delta] Hfo(Al2O3) + (2 mol)( [delta] Hfo(Fe) - (1 mol)( [delta] Hfo(Fe2O3) - (2 mol)( [delta] Hfo(Al)

Using standard values-

[delta]Horxn = (1 mol)(-1,669.8 kJ/mol) + (2 mol)(0) - (1 mol)(-822.2 kJ/mol) - (2mol)(0 kJ/mol)

[delta]Horxn = -847.6kJ

Enthalpy for the reaction = -847.6kJ