Question

Calculate the standard enthalpy change (ΔH°) for the reduction of iron(III) oxide (Fe2O3) to iron (Fe) given the following balanced chemical equation:2Fe2O3(s) + 3C(s) → 4Fe(s) + 3CO2(g)The enthalpy of formation for Fe2O3(s) is -824.2 kJ/mol and the enthalpy of formation for CO2(g) is -393.5 kJ/mol. All other substances are in their standard state.

Answer 1

To calculate the standard enthalpy change  H  for the reaction, we can use the following equation:H =  H products  -  H reactants The enthalpy of formation for Fe2O3 s  is -824.2 kJ/mol, and the enthalpy of formation for CO2 g  is -393.5 kJ/mol. The enthalpy of formation for elements in their standard state, such as C s  and Fe s , is 0 kJ/mol.Now, we can plug in the values into the equation:H = [4  0  Fe  + 3   -393.5   CO2 ] - [2   -824.2   Fe2O3  + 3  0  C ]H = [0 +  -1180.5 ] - [ -1648.4  + 0]H = -1180.5 + 1648.4H = 467.9 kJThe standard enthalpy change  H  for the reduction of iron III  oxide  Fe2O3  to iron  Fe  is 467.9 kJ.