Standard enthalpy of formation
Standard enthalpy of formation
Formula
ΔH°rxn = ΣΔH°f(products) − ΣΔH°f(reactants)
Real World
NASA chemists used standard enthalpies of formation of liquid hydrogen and oxygen to calculate the theoretical energy output of the Space Shuttle Main Engine fuel system.
Exam Focus
ΔH°f for any element in its standard state is zero — include this in Hess cycles or you will lose method marks.
How well did you know this?