What is lattice enthalpy? Give an example.

(N/A) Lattice enthalpy of an ionic solid is defined as the energy required to completely separate one mole of a solid ionic compound into its gaseous constituent ions.
Example: The lattice enthalpy of $NaCl$ is $788 \ kJ \ mol^{-1}$. This means that $788 \ kJ$ of energy is required to separate one mole of solid $NaCl$ into one mole of $Na_{(g)}^{+}$ and one mole of $Cl_{(g)}^{-}$ ions at an infinite distance.