Question

The solubility of PbSO₄ (Ksp=6.3x10⁻⁷) decreases with adding which of the following?

a. Na₂CrO₄ (Ksp of PbCrO₄=2.8x10⁻¹¹)
b. PbF₂ (Ksp of PbF₂=3.6x10⁻⁸)
c. NO₃⁻
d. Na₂S (Ksp of PbS=3x10⁻²⁸)

Answer 1

The solubility of PbSO₄ decreases with the addition of Na₂CrO₄.

Step-by-step explanation:

The solubility of PbSO4 (Ksp=6.3x10⁻⁷) decreases with adding Na₂CrO₄ (Ksp of PbCrO₄=2.8x10⁻¹¹). When Na₂CrO₄ is added, it reacts with Pb²+ to form PbCrO₄ which is highly insoluble in water. This causes a decrease in the concentration of Pb²+ ions, reducing the solubility of PbSO₄.

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