Chapter 10, Problem 2RQ

Using KF as an example, write equations that refer to ∆H_soln and ∆H_hyd· Lattice energy was defined in Chapter 3 as ∆H for the reaction K⁺(g) + F⁻ (g) → KF(s). Show how you would utilize Hess’s law to calculate ∆H_so1n from ∆H_hyd and ∆H_LE for KF, where ∆H_LE = lattice energy. ∆H_soln for KF, as for other soluble ionic compounds, is a relatively small number. How can this be since ∆H_hyd and ∆H_LE are relatively large negative numbers?