Heterogeneous Equilibria

Heterogeneous Equilibria. . . are equilibria that involve more than one phase.

CaCO3(s) CaO(s) + CO2(g)

K = [CO2]

The position of a heterogeneous equilibrium does not depend on the amounts of pure solids or liquids present.

Solubility Products (Ksp) Refer to the dissolution of a solid Temperature dependent, [solid]=1 Unique for each solid, tabulated values

In general:

KnAm nK+ + mA-

Ksp = [K+]n [A-]m

The Ksp is the ion product of a saturated solution

Precipitation and the Solubility Product:

Ksp of a salt is a quantitative statement of the

limit of solubility of the salt

1. The ion product is < Ksp The soln is unsaturated, additional solid can be dissolved in it.

2. The ion product is > Ksp The soln is super saturated, precipitation will occur.

3. The ion product = Ksp The soln is saturated

Solubility Products, Ksp

Ksp is the solubility product. The equilibrium constant for the solid dissolving to aqueous ions (solid ions).

Solubility Products, Ksp

Nearly all ionic solids dissolve somewhat in water.