Conductivity of a saturated solution of a sparingly soluble salt AB at 298 K is `1.85 xx 10^(-5) S m^(-1)`. Solubility product of the salt AB at 298 K is
Given `^^_m^(0)(AB) = 140 xx 10^(-4)S m^(2) " mol"^(-1)`

Options

A. `5.7 xx 10^(-12)`
B. `1.32 xx 10^(-12)`
C. `7.5 xx 10^(-12)`
D. `1.74 xx 10^(-12)`

Answer

D

Explanation

`S_0 = (lambda)/(lambda_0)`
`S = (k)/(1000 lambda_m) = (1.85 xx 10^(-5))/(1000 xx 140 xx 10^(-4))`
`S = 1.3 xx 10^(-6)`
`K_(sp) = S^(2) =(1.3 xx 10^(-6))^(2) = 1.69 xx 10^(-12)`