Consider an ionic compound, MX3 , composed of generic metal M and generic gaseous halogen X. The enthalpy of formation of MX3 is Δ∘f=−789 kJ/mol.
The enthalpy of sublimation of M is Δsub=179 kJ/mol.
The first, second, and third ionization energies of M are IE1=585 kJ/mol, IE2=1643 kJ/mol, and IE3=2719 kJ/mol .

The electron affinity of X is ΔEA=−333 kJ/mol . (Refer to the hint).

The bond energy of X2 is BE=245 kJ/mol.
Determine the lattice energy of MX3.