Solubility Product Constant Handout

Solubility Product Constant
Q:

Write the equilibrium equation for a saturated solution of the following salts and the corresponding solubility product expressions.
a) BaSO4 (s)
b) MgF2 (s)
c) Ag2S (s)
d) Cu(IO3)2 (s)
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What is the equilibrium concentration of Cd2+ ions in a saturated solution made by shaking CdS(s) with water? Ksp = 6.0x10-27 for CdS.
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A solution in equilibrium with a precipitate of AgCl was found to contain
3.4x10-6M Cl . Calculate Ksp for AgCl.
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Q:

Since the value of Ksp depends on the concentrations of the ions in solution, a larger value of Ksp indicates a more soluble salt, while a smaller value of Ksp indicates a less soluble salt. Which of the following salts is the most soluble?
AgCl (Ksp = 1.8x10-10)
AgI (Ksp = 8.5x10-17)
-13
AgBr (Ksp = 5.4x10 )

A:

AgCl is most soluble (it has the largest Ksp, therefore, largest s)

Q:

Calculate the molar solubility of Ag2SO4 in 1.0M NaSO4. Ksp = 1.4x10-5

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Using the concentration table:
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Neglecting s on the second factor,
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Ksp = 5.0x10-22 for CoS. Will a precipitate form when 1.0 L of 3.0x10-10 M Co2+ is added to 1.0 L of 2.0x10-11
2MS ?
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, then a precipitate will form.

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