Question:
As per Hardy-Schulze formulation, the flocculation values of the following for ferric hydroxide sol are in the order:
Correct Option: 1
Solution:
According to Hardy-Schulte,
Coagulation value or fluocculation value
$\propto \frac{1}{\text { Coagulation power }}$
order of coagulation power:
$\mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]>\mathrm{K}_{2} \mathrm{CrO}_{4}>\mathrm{KBr}=\mathrm{KNO}_{3}=\mathrm{AlCl}_{3}$
$\therefore \quad$ order of flocculation value :
$\mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]<\mathrm{K}_{2} \mathrm{CrO}_{4}<\mathrm{KBr}=\mathrm{KNO}_{3}=\mathrm{AlCl}_{3}$