Which of the following alkaline earth metal sulphates is least soluble in water?

Question

Which of the following alkaline earth metal sulphates is least soluble in water? (A) BaSO 4 (B)  MgSO4 (C)  SrSO4  (D)  CaSO4

Tardigrade Admin · Accepted Answer

The solubility of the alkaline earth metal sulphates in Water decreases down the group, because of the decrease in hydration energy due to increase in atomic size ie,

B e > M g >> C a > S r > B a

.
Remember, in case of sulphates of alkaline earth metals lattice energy remains almost constant as the size of metal increases, thus solubility is decided only by hydration energy.
Hence,

B a S O_{4}

is least soluble in water.

Q. Which of the following alkaline earth metal sulphates is least soluble in water?

$B a S O_{4}$

$M g S O_{4}$

$S r S O_{4}$

$C a S O_{4}$

Q. Which of the following alkaline earth metal sulphates is least soluble in water?

BaSO4​

MgSO4​

SrSO4​

CaSO4​

$B a S O_{4}$

$M g S O_{4}$

$S r S O_{4}$

$C a S O_{4}$