Consider an ionic compound, MX₃, composed of generic metal M and generic gaseous halogen X.

The enthalpy of formation of MX₃, is H_f: = -729 kJ/mol.

The enthalpy of sublimation of M is H_sub = 175 kJ/mol.

The first, second, and third ionization energies of M are IE1 = 615 kJ/mol, IE₂ = 1697 kJ/mol, and IE₃ = 2611 kJ/mol.

The electron affinity of X is H_EA= -373 kJ/mol. (Refer to the hint).

The bond energy of X₂, is BE = 157 kJ/mol.

Determine the lattice energy of MX_3.