Q.

1×10-5 M AgNO3 is added to 1 L of saturated solution of AgBr. The conductivity of this solution at 298 K is _________ ×10-8 S m-1.

[Given: Ksp(AgBr)=4.9×10-13 at 298 K

λAg+=6×10-3 S m2mol-1

λBr-=8×10-3 S m2mol-1

λNO3-=7×10-3 S m2mol-1]                            [2023]


Ans.

(13040)

10-5 M AgNO3 is added to saturate AgBr.

            Ksp=(s+10-5)(s)

                   =s(10-5)=4.9×10-13

                s=4.9×10-8

Solution has

       [Ag+]=10-5, [NO3-]=10-5

        [Br-]=5×10-8

              λ=K×1000C

          KTotal=λ1C11000+λ2C21000+λ3C31000

6×10-3×104×10-51000+7×10-3×104×10-51000+8×10-3×104×5×10-81000

6×10-7+7×10-7+40×10-10

=13.04×10-7 S cm-1=13.04×10-5 S m-1

=13040×10-8 S m-1

=13040