ABSTRACT
At 25°C, KSP for AgI has a value of 1.5 × 10 –16. For salts with such low solubilities, the concen-
trations in solution are so dilute that we can safely set ai 5 1, and ai 5 mi 5 ci. Therefore,
KSP (AgI) = [Ag ] + [I ]< = 1.5 × 10-16
s A s s
If s is the solubility of AgI, in mol L-1, then [Ag ](aq) + = [I ](aq)
Fig. 1
and KSP = [Ag ](aq) + [I ](aq)
from which s = KSP = 1 5 10 16. × < = 1.22 × 10-8 . . . [3]
Therefore the solubility of AgI in water at 25°C is 1.22 × 10-8 mol L-1.
