Question

Baso4 is sparingly soluble in water where as Ba(OH)2 has high solubility in water why? Expalin with proper reason.​

Answer 1

• BaSO₄ is sparingly soluble in water due to its more lattice energy. But lattice energy plays no role in solubility.
• Whereas Ba(OH)₂ has high solubility because of its high hydration energy.
• For OH⁻ ion while moving down the group they become more soluble.
• This is because the size of the cation increases down the group which means the distance between center of mass between cation and anion increases.
• This leads to the increase in the hydration energy and decrease in lattice energy.
• In case of BaSO₄ hydration energy decreases and lattice energy increases.
• That's why BaSO₄ is sparingly soluble where as Ba(OH)₂ is completely soluble in water.

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