Question

The highest lattice energy corresponds to

• A. MgO
• B. CaO
• C. SrO
• D. BaO

Answer 1

Answer: (A)

MgO

Answer 2

Lattice energy $\propto$ charge of ion $\propto \frac{1}{\text { size of ion }}$
On moving downward, the size of alkaline earth metals increases due to increase in number of shells.
Thus, $Mg$ has the smallest size. Hence, lattice energy is highest for $MgO$.