The AM1 valence electronic energies of the atoms H and O are - 11.396 eV and -316.100 eV, respectively. For H2O at its AM1-calculated equilibrium geometry, the AM1 valence electronic energy (core-core repulsion omitted) is -493.358 eV and the AM1 core-core repulsion energy is 144.796 eV. For H(g) and O(g), ∆Hof,298 values are 52.102 and 59.559 kcal/mol, respectively. Find the AM1 prediction of ∆Hof,298 of H2O1g2. The experimental value is -57.796 kcal/mol.