Also known as the law of heat summation, FTP, name this law that states that the total energy change for a chemical reaction is the same regardless of the route that is taken.
It is frequently used to measure lattice energies, and is solely dependent upon the final state of the reactants and products.  It is even more useful in calculating the enthalpy change of a reaction that can not be measured directly.  Also known as the law of heat summation, FTP, name this law that states that the total energy change for a chemical reaction is the same regardless of the route that is taken.
It is frequently used to measure lattice energies, and is solely dependent upon the final state of the reactants and products.  
Hess' law