Question

`K_(sp)` of `PbBr_(2)` is `8 xx 10^(-5)`. If the salt is `80%` dissociated in solution, calculat the solubility of salt in `gL^(-1)`.

Answer 1

Let solubility of `{:(PbBr_(2)(s)hArr,PbBr_(2)(aq)hArr,Pb^(2+)+,2Br^( Θ),),(,,(Sxx80)/(100),(2Sxx80)/(100),):}`
Ionisation of `PbBr_(2)(s) = 80%`
`:. K_(sp) = [Pb^(2+)] [Br^(Θ)]^(2)`
`8 xx 10^(-5) = ((Sxx80)/(100)) ((2S xx 80)/(100))^(2)`
`:.S = 0.034 mol L^(-1) (M.wt of PbBr_(2) = 367)`
`S = 0.034 xx 367 gL^(-1) = 12.48gL^(-1)`