Question

100 ml Na2CrO4 solution on mixing with 400 ml of 0.1 M AgNO3 just initiates precipitation of Ag2CrO4. what is the molarity of Na2CrO4.Ksp (Ag2Cro4)=1.6×10^-10

Answer 1

Answer:

Ag2Cr→2Ag++CrO42

1                     0             0

1-s                2s           s           

Ksp=1−s(2s)2s, s< < 1

=1.1×10−12=4s3

=s=6.5×10−5

AgCl→Ag++Cl−

                s              s

1.8×10−10=s2

=s=1.34×10−5

silmilarly s for AgBr and AgCl is 7.1×10−7 and 9×10−9 respectively since solubility of Ag2CrO4 is lighest, sa it will perticipate lost