Question

Calculate the standard enthalpy change for the reaction: 2Fe(s) + 3/2O2(g) → Fe2O3(s), given that the standard enthalpy of formation for Fe2O3(s) is -824.2 kJ/mol, the standard enthalpy of formation for Fe(s) is 0 kJ/mol, and the standard enthalpy of formation for O2(g) is 0 kJ/mol.

Answer 1

To calculate the standard enthalpy change for the reaction, we can use the following formula:H =  Hf products  -  Hf reactants where H is the standard enthalpy change for the reaction, and Hf is the standard enthalpy of formation for each compound.For this reaction, we have:H = [1  Hf Fe2O3 ] - [2  Hf Fe  + 3/2  Hf O2 ]Given the standard enthalpies of formation:Hf Fe2O3  = -824.2 kJ/molHf Fe  = 0 kJ/molHf O2  = 0 kJ/molSubstitute the values into the formula:H = [1   -824.2 ] - [2  0 + 3/2  0]H = -824.2 kJ/molTherefore, the standard enthalpy change for the reaction is -824.2 kJ/mol.