Predict and explain how the enthalpy change of hydration varies for the ions $\text{F}^-$, $\text{Cl}^-$, $\text{Br}^-$ and $\text{I}^-$.
Fig. 2.1 illustrates an incomplete energy cycle for calcium fluoride, $\text{CaF}_2$. Complete line D. Add state symbols.
The enthalpy change for process 1 may be worked out from five other enthalpy changes that are not mentioned in Fig. 2.1. Process 1: $\text{Ca}(s) + \text{F}_2(g) \rightarrow \text{Ca}^{2+}(g) + 2\text{F}^-(g)$. Identify these five other enthalpy changes, using either names or symbols.
Fig. 2.1 illustrates an incomplete energy cycle for calcium fluoride, $\text{CaF}_2$.
Define lattice energy, $\Delta H_{\text{latt}}$, in words.
Complete the expression so that it shows the mathematical link between $\Delta H_{\text{latt}}$ of calcium fluoride and the enthalpy changes for processes 1 and 3. $\Delta H_{\text{latt}} =$
Use the data in Table 2.1 to calculate the hydration energy, $\Delta H_{\text{hyd}}$, of fluoride ions, $\text{F}^-\text{(g)}$. $\Delta H_{\text{hyd}}\ \text{F}^-\text{(g)} = \ldots\ldots\ldots\ldots\ldots\ldots\ldots\ldots\ \text{kJ mol}^{-1}$
Define entropy in physical terms.
At $298\ \text{K}$, the Gibbs free energy change, $\Delta G$, for dissolving compound T is $+6.00\ \text{kJ mol}^{-1}$. The enthalpy change of solution, $\Delta H_{\text{sol}}$, of compound T is $+30.0\ \text{kJ mol}^{-1}$ at $298\ \text{K}$. Calculate the value of the entropy change, $\Delta S$, for the solution of compound T at $298\ \text{K}$. $\Delta S = \ldots\ldots\ldots\ldots\ldots\ \text{J K}^{-1}\ \text{mol}^{-1}$
Predict whether compound T becomes more soluble or less soluble as the water is heated from $298$ to $360\ \text{K}$. Explain your answer.