`BaSO_(4)` is insoluble in water, even though it is an ionic compound. Why?

Explanation

The lattice energy (i.e., energy required to break its crystal lattice, by separating `Ba^(2+) and SO_(4)^(2-)` ion) of `BaSO_(4)` is greater than its solvation enegy (i.e., energy released due to solvation of `Ba^(2+) and SO_(4)^(2-)` ions by water molecules).hence, `BaSO_(4)` is insoluble in water.)