As per Hardy-Schulze formulation,

Download now India's Best Exam Prepration App Class 8-9-10, JEE & NEET
Video Lectures	Live Sessions
Study Material	Tests
Previous Year Paper	Revision

Video Lectures

Live Sessions

Study Material

Tests

Previous Year Paper

Revision

Question:
As per Hardy-Schulze formulation, the flocculation values of the following for ferric hydroxide sol are in the order:

$\mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]<\mathrm{K}_{2} \mathrm{CrO}_{4}<\mathrm{KBr}=\mathrm{KNO}_{3}=\mathrm{AlCl}_{3}$
$\mathrm{~K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]<\mathrm{K}_{2} \mathrm{CrO}_{4}<\mathrm{AlCl}_{3}<\mathrm{KBr}<\mathrm{KNO}_{3}$
$\mathrm{AlCl}_{3}>\mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]>\mathrm{K}_{2} \mathrm{CrO}_{4}>\mathrm{KBr}=\mathrm{KNO}_{3}$
$\mathrm{~K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]>\mathrm{AlCl}_{3}>\mathrm{K}_{2} \mathrm{CrO}_{4}>\mathrm{KBr}>\mathrm{KNO}_{3}$

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 :

$\mathrm{K}_{3}\left[\mathrm{Fe}(\mathrm{CN})_{6}\right]<\mathrm{K}_{2} \mathrm{CrO}_{4}<\mathrm{KBr}=\mathrm{KNO}_{3}=\mathrm{AlCl}_{3}$