7.68 The solubility product constant of Ag2CrO4 and AgBr are 1.1 × 10–12 and
5.0 × 10
–13 respectively. Calculate the ratio of the molarities of their saturated solutions.

LetsbethesolubilityofAg2CrO4.
Then,AggCrO4Ag2++2CrO4-
Ksp=(2s)2.s=4s3
1.1×10-10=4s
s=6.5×10-5M
Lets'bethesolubilityofAgBr.
AgBr(s)Ag++Br-
Ksp=S'2=5.0×10-13
s'=7.07×10-7M
Therefore,theratioofthemolaritiesoftheirsaturatedsolutionis
2s'=6.5×10-5M7.07×10-7M=91.9.