When `1.88 g` of AgBr(s) is added to a `10^(-3)` M aqueous solution of KBr, the concentrationof Ag is `5xx10^(-10)`M. If the same amout of AgBr(s) is added to a `10^(-2)` M aqueous solution of `AgNO_(3)`, the concentration of `Br^(-)` is

Options

A. `9.4xx10^(-9)M`
B. `5xx10^(-10)M`
C. `1xx10^(-11)M`
D. `5xx10^(-11)M`

Answer

D

Explanation

`K_(sp(AgBr))=[Ag^(+)][Br^(-)]`
`=(5xx10^(-10))(10^(-3))`
`=5xx10^(-13)`
Now
`5xx10^(-13)=(10^(-2))[Br]`
`[Br^(-)]=5xx10^(-11)M`