(a)[4]
Describe how the solubility of the sulfates of magnesium, calcium and strontium changes. Give an explanation for your answer. Say which sulfate is the most soluble and which is the least soluble.
(b)[2]
Define the term lattice energy, $\Delta H_{\text{latt}}$.
(c)[2]
State and explain the main factors that influence the size of lattice energies.
(d(i))[3]
Born-Haber cycles are used to work out lattice energies of ionic compounds. Complete the Born-Haber cycle in Fig. 1.1 for potassium sulfide, $\text{K}_2\text{S(s)}$. Add state symbols for every species.
(d(ii))[2]
Calculate the lattice energy, $\Delta H^{\circ}_{\text{latt}}$, of $\text{K}_2\text{S(s)}$ using the relevant data from Table 1.1. Show your calculations.