Answer to Question #303908 in General Chemistry for Lea

Question

Calculate the standard change in enthalpy for the given reaction:

2 Al(s) + Fe₂O₃(s) → Al₂O₃ (s) + 2 Fe(s)

Given:

ΔH° Fe₂O₃ (s) = -826 kJ/mol

ΔH° Al₂O₃ (s) = -1676 kJ/mol

Answer 1

ΔH°_rxn = ΔH°_products - ΔH°_reactants = [2xΔH°(Fe_(s)) + ΔH°(Al₂O_3(s))] - [ΔH°(Fe₂O_3(s)) + 2xΔH°(Al_(s))] = [2 x 0 + (-1676 kJ)] - [(-826) + 2 x 0] = -850 kJ