Question

The volume of the water needed to dissolve $1$g of $Ba{SO}_4$ ($K_{sp}=1.1\times {10}^{-10}$) at ${25}^{o}C$ is:

• A. 100 lit
• B. 200 lit
• C. 410 lit
• D. 600 lit

Answer 1

The correct option is C 410 lit

Solubility of $Ba{SO}_4=\sqrt{K_{sp}}=\sqrt{1.1\times {10}^{-10}}=1.05\times {10}^{-5}M$

$\therefore$ mass of $Ba{SO}_{[}4=1.05\times {10}^{-5}\times 223$

or $w_{Ba{SO}_4}=244.27\times {10}^{-5}g/litre$

$\therefore$ Volume of water needed to dissolve $1gBa{SO}_4$ is equal to $\frac{1}{244.27\times {10}^{-5}}=410$ litre