# Which of the following ions would be expected to have the greater energy of hydration, Mg^(2+) or Al^(3+)?

Well, which ion has the greater $\text{nucular charge}$?
Clearly, $\text{aluminum}$ has a GREATER nuclear charge than magnesium... And it is ALSO a formal $A {l}^{3 +}$ trication…and also also it is a trication as opposed to a dication...