Want to seperate them

Songei
First ionization energy of $Na$ is $494 kJ•mol^{-1}$ and electron affinity of $Cl$ is $349 kJ•mol^{-1}$ .

$642 kJ$ is released when 1 mol of gaseous $Na$ atom react with 1 mol of gaseous $Cl$ atom to form 1 mol of $NaCl$ solid.

Calculate the lattice energy ( $KJ$ ) of $NaCl$ .

Gene
First ionization energy of $\text{Na}$ is $494 \text{ kJ} \cdot \text{mol}^{-1}$ and electron affinity of $\text{Cl}$ is $349 \text{ kJ} \cdot \text{mol}^{-1}$ . And $642 \text{ kJ}$ is released when $1 \text{ mol}$ of gaseous $\text{Na}$ atom react with $1 \text{ mol}$ of gaseous $\text{Cl}$ atom to form $1 \text{ mol}$ of $\text{NaCl}$ solid.
Calculate the lattice energy (in $\text{kJ}$ ) of $\text{NaCl}$ .