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, arrange these compounds by their expected lattice energy. Note that many sources define lattice energies as negative values. Please arrange by magnitude and ignore the sign. |lattice energy|=absolute value of the lattice energy Greatest|lattice energy|. RbCl ,RbBr ,Rbl ,RbF.
As stated in the question, the latice energy depends on the relative size of the ions. When the action size is constant as in the question, the lattice energy now depends on the relative of the anions. The order of increase in ionic sizes among the halide ions is fluoride<Chloride<Bromide<Iodide. This order of increasing size means that the lattice energy will decrease accordingly as shown in the answer.
