The coagulation of 200 ~mL of a positive colloid took place when 0.73 ~g HCl was added to it without changing the volume much. The flocculation value of HCl for the colloid is

Step-by-step solution

: 200 ~mL of the sol required =0.73 ~g HCl = 0.73 36.5 =0.02 ~mol =20 mmol 1000 ~mL (1 ~L ) of the sol will require = 20 200 1000=100 mmol Thus, the flocculation value of HCl for the colloid is 100 .