1. Solubility Product
KSP

2. Please Write Solubility:
Is the maximum amount of a substance that can dissolve in a given volume of solvent.
Dependent on temperature.
mol/L or g/L
Unsaturated solution:
More solute can be dissolved.
Saturated solution:
Any solute added will precipitate out.
An equilibrium is formed:
Solute (s) ⇆ + ion (aq) ion (aq)
Dissolved Ions
Solid Solute

3. Ksp - solubility product
Please Write
AgCl(s)⇆ Ag+(aq) + Cl-(aq)
Ksp = [Ag+][Cl-]
If the ion concentration is high:
Ksp >1
High solubility
Substance is “soluble”
If the ion concentration is low:
Ksp <1
Low solubility
Substance is “insoluble”

4. Ex. 1 If the solubility of BaSO3 is 0.0025g/L, find the Ksp.
Please Write
BaSO3(s)⇆ Ba2+(aq) + SO32-(aq)
Ksp = [Ba2+][SO32-]
Ex. 1 If the solubility of BaSO3 is g/L, find the Ksp.
Since it dissociates with 1:1, the [Ba2+] & [SO32-] = #moles of BaSO3 dissolved ( g/L).
We have to convert g/L into mol/L
1 𝑚𝑜𝑙 𝐵𝑎𝑆𝑂3 𝑥 = 217.4𝑔 𝑔
x = 1.15x10-5 mol/L
So [Ba2+] = [SO32-] = 1.15x10-5 mol/L
Ksp = [Ba2+][SO32-] =(1.15x10-5)(1.15x10-5) = 1.32x10-10

5. Ex.2 What is the solubility Al(OH)3? Ksp = 2.6 x 10-39
Please Write
Ex.2 What is the solubility Al(OH)3? Ksp = 2.6 x 10-39
Al(OH)3 (s)  Al+3 (aq) + 3OH- (aq)
1 : 1 : 3
Ksp = [Al+3][OH-]3
2.6 x = [x][3x]3
Al(OH)3 = 9.9 x M
2.6 x = 27x4

6. Ksp practice questions
If the dissociation of Calcium chloride produces a solution containing a concentration of mol/L of Calcium ions and mol/L of Chloride ions, what is the Ksp of the reaction?
If the solubility of MgF2 is 1.30×10-4 g/100 mL, find the Ksp of this reaction.
If the Ksp of barium cyanide, Ba(CN)2, is at 25°C, find the concentration of deadly cyanide ions (CN-) at equilibrium.