Question

Calculate the standard enthalpy change for the formation of carbon dioxide (CO2) from its elements, given the following standard enthalpies of formation:ΔHf°(CO2) = -393.5 kJ/molΔHf°(C) = 0 kJ/molΔHf°(O2) = 0 kJ/mol

Answer 1

The standard enthalpy change for the formation of carbon dioxide  CO2  from its elements can be calculated using the given standard enthalpies of formation. The balanced chemical equation for the formation of CO2 is:C  s  + O2  g   CO2  g Since the standard enthalpies of formation for carbon  C  and oxygen  O2  are both 0 kJ/mol, the standard enthalpy change for the formation of CO2 is equal to the standard enthalpy of formation for CO2 itself:Hf CO2  = -393.5 kJ/molTherefore, the standard enthalpy change for the formation of carbon dioxide  CO2  from its elements is -393.5 kJ/mol.