Ions in solution - Common Ion Effect - Solubility Product Constant Ksp
Common Ion Effect - The concentrations of ions in solution are affected by all equilibria
and all species present in the solution. The common ion effect is simplest and most
significant such effect.
The common ion effect is observed whenever an ion in solution is common to two
different salts which serve as its sources. Addition of the second
salt adds the common ion, which is a product of the dissolution of
the first. The effect of adding the product ion will be to decrease
the solubility of the first salt.
If a salt M1xA1y (e.g. BaF2 : x=1, y=2) is added
into a solution already containing a common ion e.g. M2+m
(Ba+2), the expression for the solubility product will be:
Ksp=[M1+m+M2+m]x [A1-a]y
Solubility Calculator - Rules , Product and Constant
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