Question

Find the decreasing order of lattice energy in naf,nacl,nabr

Answer 1

Explanation:

decompose the ionic solid into its constituent cation and anion is called lattice energy.

For example, in the formation of sodium chloride from sodium ion and chloride ion in gaseous state, 787.3 kj/mol of energy gets released, which is known as the lattice energy of sodium chloride.

The same amount of energy will be used in the decomposition of this ionic solid into its constituent ions.

Overall as we go down in a group, ionic radius increases and lattice energy decrease. However, in a period from left to right as the charge on ion increases, lattice energy increases.

Lattice energy∝

size of the ion

Charge on ion

So the correct order of lattice energy is NaI<NaBr<NaCl<NaF