Question

The hydration energy of $M{g}^{2+}$ is:

• A. more than that of $M{g}^{3+}$ ion
• B. more than that of $N{a}^{+}$ ion
• C. more than that of $A{l}^{3+}$ ion
• D. more than that of $B{e}^{2+}$ ion

Answer 1

Answer: (B)

more than that of $N{a}^{+}$ ion

Hydration energy depends on charge of ion and ionic radius. 

Higher the charge, greater the hydration energy. On the other hand, smaller the size, 

greater the hydration energy. 

Charge is considered first for comparison. Hence, Mg2+ has higher hydration energy than Na+.