For any sparingly soluble salt `[M(NH_(3))_(4)Br_(2)] H_(2)PO_(2)`
Given: `lambda_(M(NH_(3))_(4)Br_(2)^(+))^(@) = 400 Sm^(2) - mol^(-1)`.
`lambda_(H_(2)PO_(2)^(-))^(@) = 100 S-m^(2) -mol^(1)`
Specific resistance of saturated `[M(NH_(3))_(4)Br_(2)] H_(2)PO_(2)` solution is `200 Omega-cm`
If solubility product constant of the above salt is `10^(-x)`. What will be the value of `x`.

Answer

16

Explanation

`^^_(m)^(oo) = K xx(1000)/(m) xx 10^(-6)`
`500 = (1)/(200) xx (1000)/(5) xx 10^(-6)`
`S = 10^(-8) mol//L`
`K_(sp) = S^(2) = 10^(-16)`