On adding solution into KI solution, a negatively charged colloidal sol is obtained when they are in

Reaction,

${\text{AgNO}}_{\text{3}}+\text{KI}\to \text{AgI}+{\text{KNO}}_{\text{3}}$

50 ml of 0.01 M ${\text{AgNO}}_{\text{3}}+50\text{\hspace{0.17em}ml}$ of 0.2 N KI

m moles of            $AgN{O}_3=50\times 0.1=5$

m moles of             $KI=50\times 0.2=10$

KI – Excess negatively charged colloidal sol is obtained when KI solution must be in excess.