The lattice energy required to separate the ions in a hypothetical salt XCl2 is +2520kJ mol−1, and the hydration enthalpy for the ions once they are dispersed in water is −2440kJ mol−1. What is the enthalpy change for the overall dissolution process, ΔHsoln, for one mole of XCl2?
a) −80kJ mol−1
b) +4960kJ mol−1
c) +80kJ mol−1
d) −2360kJ mol−1