Question

Assertion: $N{a}_{2}S{O}_4$ is soluble in water while $BaS{O}_4$ is not.
Reason: Lattice energy of $BaS{O}_4$ exceeds its hydration energy.

• A. If both Assertion and Reason are true and the Reason is a correct explanation of the Assertion
• B. If both Assertion and Reason are true but Reason is not a correct explanation of the Assertion
• C. If Assertion is true but the Reason is false
• D. If both Assertion and Reason are false

Answer 1

Answer: (A)

The large sized sulphate anion $(S{O}_4^{2-})$ is stabilised better by a large sized cation. So the stability of sulphates down the group, increases. In other words lattice energy is more down the group.