The radii of the sodium and potassium ions are 102 pm and 138 pm, respectively. which compound has stronger ionic at - tractions, sodium chloride or potassium chloride?

The NaCl has more attraction as compare to KCl.

Explanation:

As we know down the group size is increases. As the size of K is greater than Sodium. Due to greater size of atom, the distance between the K and Cl is greater than NaCl. Due to greater distance between the atoms, attraction become less.

Summary:

Greater size (greater radius) between atoms, lesser will be attraction.