Born-Haber cycles are called cycles because they form closed loops. If any five of the six energy changes in the cycle are known, the value of the sixth can be calculated.

Use the following five values to calculate a lattice energy (in kilojoules per mole) for sodium hydride, NaH:

Eea for H = -72.8 kJ/mol

Ei1 for Na = +495.8 kJ/mol

Heat of sublimation for Na = +107.3 kJ/mol

Bond dissociation energy for H2 = 435.9 kJ/mol

Net energy change for the formation of from its elements = -60 kJ/mol.