Final answer:
Among RbCl and SrCl2, SrCl2 has the larger lattice energy due to its larger product of ionic charges, which are (+2)(-1)(2) = -4 compared to RbCl's (+1)(-1) = -1.
Step-by-step explanation:
The student has inquired about which compound has a larger lattice energy, RbCl or SrCl2. Lattice energy is related to the strength of the ionic bonds within an ionic crystal. It is directly proportional to the product of the ionic charges and inversely proportional to the internuclear distance between the ions.
Since RbCl is composed of Rb+ and Cl− ions, it has products of charges equal to (+1)(−1) = −1. SrCl2, on the other hand, has Sr2+ and two Cl− ions, leading to a products of charges equal to (+2)(−1)(2) = −4. Consequently, SrCl2, with a larger product of ionic charges, would have a stronger ionic bond and, hence, a larger lattice energy.
Therefore, amongst the options given, b) SrCl2 has the larger lattice energy.