on adding `AgNO_(3)` solution into KI solution , a negatively charged colloidal sol is obtained when they are in :

Explanation

The charge on the colloidal particles upon the preferential adsorption of the ions from the electrolyte that are common with their own littice ions. When `AgNO_(3)` is added to an aqueous solution of Kl, the yellow precipitate of AgI adsorb `I_(-)` ions from the electrolyete KI and forms negatively charged colloidal particles.
`AgI+KI to underset(("fixed part"))([AgI]I^(-)) : underset(("diffused part"))(NO_(3)^(-))`
When formed on adding kI solution to an aqueous solution of `AgNO_(3)` , Positivelt charged `Ag^(+)` ions are adsorbed from the electrolyte and the collouidal particles acquire negative charge.
`" "AgI+AgNO_(3)to underset(("fixed part"))([AgI]Ag^(+)) : underset(("diffused part"))(NO_(3)^(-))`