Draw diagram to show four water molecules hydrating a magnesium ion. Show the dipole on each water molecule.

Draw diagram to show two water molecules hydrating a bromide ion. Show the dipole on each water molecule.

Explain why the value of $∆{\mathrm{H}}_{\mathrm{hyd}}^{⊝}$ for magnesium ions is much more exothermic than $∆{\mathrm{H}}_{\mathrm{hyd}}^{⊝}$ for potassium ions.

Name the change associated with the equation below:

$\mathrm{KBr}\left(\mathrm{s}\right) + \mathrm{aq} \to \mathrm{KBr}\left(\mathrm{aq}\right)$ (for $1 \mathrm{mole}$ of $\mathrm{KBr}$)

Name the change associated with the equation below:

${\mathrm{K}}^{+}\left(\mathrm{g}\right) + \mathrm{aq}\to {\mathrm{K}}^{+} \left(\mathrm{aq}\right)$ (for $1 \mathrm{mole}$ of ${\mathrm{K}}^{+}$ ions)

Name the change associated with the equation below:

${\mathrm{K}}^{+} \left(\mathrm{g}\right) + {\mathrm{Br}}^{-} \left(\mathrm{g}\right) \to \mathrm{KBr}\left(\mathrm{s}\right)$ (for $1 \mathrm{mole}$ of $\mathrm{KBr}$)

Name the change associated with the equation below:

${\mathrm{Br}}^{-} \left(\mathrm{g}\right) + \mathrm{aq}\to {\mathrm{Br}}^{-} \left(\mathrm{aq}\right)$ (for $1 \mathrm{mole}$ of ${\mathrm{Br}}^{-}$)

Draw an energy cycle to calculate the enthalpy of hydration of magnesium ions when magnesium chloride dissolves in water.

Calculate the enthalpy of hydration of magnesium ions given that:
$$\begin{gathered} ∆{\mathrm{H}}_{\mathrm{latt}}^{⊝} \left[{\mathrm{MgCl}}_2\right] =-2592 \mathrm{kJ} {\mathrm{mol}}^{-1} \\ ∆{\mathrm{H}}_{\mathrm{sol}}^{⊝} \left[{\mathrm{MgCl}}_2\right]=-55 \mathrm{kJ} {\mathrm{mol}}^{-1} \\ ∆{\mathrm{H}}_{\mathrm{hyd}}^{⊝} \left[{\mathrm{Cl}}^{-}\right]=-364 \mathrm{kJ} {\mathrm{mol}}^{-1} \end{gathered}$$

(Give the value only)