The question is incomplete, the complete question is:
In an ionic compound, the size of the ions affects the internuclear distance (the distance between the centers of adjacent ions), which affects lattice energy (a measure of the attractive force holding those ions together). Based on ion sizes, rank these compounds of their expected lattice energy..
Note: Many sources define lattice energies as negative values. Please rank by magnitude and ignore the sign. |Lattice energy| = absolute value of the lattice energy.
RbCl ,RbBr ,Rbl ,RbF
Answer:
RbF> RbCl>RbBr>RbI
Explanation:
As it was rightly stated in the question, the lattice energy depends on the size of the ions and their distance if separation according to Coulomb's law.
Looking at the ionic salts stated, the action size is the same but the anion sizes vary. The smaller, the anion size, the higher the lattice energy.
Since ionic size increases steadily from Fluorine to iodine, lattice energy decreases in that order since the distance of separation of the ions increases as the ions become larger. Hence the answer.
