Consider an ionic compound, MX2, composed of generic metal M and generic, gaseous halogen X. The enthalpy of formation of MX2 is -861 kJ/mol. The enthalpy of sublimation of M is 161 kJ/mol. The first and second ionization energies of M are 739 kJ/mol and 1368kJ/mol. The electron affinity of X is -323 kJ/mol. The bond energy of X2 is 157 kJ/mol. Determine the lattice energy of MX2.