Final answer:
BaS has a higher lattice energy than CsCl.
Step-by-step explanation:
The compound with the higher lattice energy between BaS and CsCl is BaS. This is because lattice energy is directly proportional to the product of the ionic charges and inversely proportional to the internuclear distance. In BaS, both the cation (Ba²+) and the anion (S²-) are larger than the corresponding ions in CsCl, resulting in a greater internuclear distance and lower lattice energy.