AP Chemistry / Unit 7: Equilibrium
7.12 Common-Ion Effect
Notes
Adding an ion already in the equilibrium shifts it left, lowering the salt's solubility.
Practice
AgCl is least soluble in:
Added $\mathrm{Cl^-}$ shifts the equilibrium left.
Adding $\mathrm{Ag^+}$ to a saturated AgCl solution:
Shift left.
The common-ion effect changes:
$K_{sp}$ stays the same.
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