Question

The K_sp for BaSO₄ is 1.08x10^-10. Which solution of BaSO₄ will dissolve the least?

A. BaSO₄ in a 0.01 M solution of sodium sulfate.

B. BaSO₄ in a 0.10 M solution of barium nitrate.

C. BaSO₄ in a 0.10 M solution of sodium nitrate.

D. BaSO₄ in a 0.10 M solution of calcium chloride.

E. BaSO₄ in a 0.10 M solution of sodium chloride.

Answer 1

Due to the common ion effect the solubility is decreses.

BaSO4 ------> Ba^2+(aq) + SO4^2-(aq)

Here the ions are Ba^2+ and SO4^2-

Options A sodium sulfate has the common ion SO4^2-

So it has low solubility.

Options B barium nitrate has the common ion Ba^2+

So it has low solubility

Option C,D and E are not having the common ions. So these three are not correct options.

Now come to options A and B. In option A concentration is 0.01 M and in option B concentration is 0.10 M. So the solution with more concentration has low solubility.

Hence the correct option is (B)