Question

if ionic nature increass then lattice energy increases or decreases.

Answer 1

Lattice energy decreases as ionic radius increases.

The lattice energy is the amount of energy required to completely

separate a mole of the solid ionic compound into its gaseous ions. As an example, if the ionic radius decreases and the ionic charges increase, the ions will be held closer and tighter. As a result of this, more energy will be needed to separate the ions.

Answer 2

As the charge of the ions in the bond increases and the atomic radius of the ions decreases/as the charge density of the oppositely charged ions increases, the lattice energy increases as the ions are brought closer together. ... Thus, the strength of the bond increases, but the bond is not more 'ionic'.