Question

For the coagulation of a negative sol, the species below, that has the highest flocculating power is?

• A. $\mathrm{SO}{2}^{-4}$
• B. ${\mathrm{Na}}^{+}$
• C. ${\mathrm{Ba}}^{2+}$
• D. ${\mathrm{PO}}_4^{-3}$

Answer 1

The correct option is C

${\mathrm{Ba}}^{2+}$

Explanation for the correct option:

1. A positive ion is required for flocculation for a negative sol $\mathrm{A}$.
2. Hardy Schulz states that greater the valency of oppositely charged ion of electrolyte which is being added, then faster will be the coagulation.
   Therefore, ${\mathrm{Ba}}^{2+}$ has highest flocculating power.

Hence, option C is correct.

Explanation for the incorrect option:

(A) The Hardy rule statement clearly explains that option (A) is incorrect.

(B) The Hardy rule statement clearly explains that option (B) is correct.

(D) The Hardy rule statement clearly explains that option (D) is correct.