1 Calculate the molar solubility of bbarium sulfate BaSO4 in

1. Calculate the molar solubility of bbarium sulfate, BaSO4, in 0.010 M Sodium Sulfate, Na2SO4, solution at 25C. Compare this to the solubility of BaSO4 in pure H2O. What is the common ion?

2. We mix 100 mL of 0.010 M Potassium Sulfate, K2SO4, and 100 mL of 0.10 M lead (II) nitrate, Pb(NO3)2, solutions. WIll a precipitate form?

Solution

1. The solubility of barium sulphate will be more in water. The common ion is sulphate ion. Due to common ion effect the solubility is suppressed in sodium sulphate. 2. [Pb][SO42-] > 1.6 * 10 ^ -8 So precipate will form as product exceeds Ksp.