Question

A sol has positively charged colloidal particles. Which of the following solutions is required in lowest concentration for coagulation -

• A. NaCl
• B. $K_4\left[Fe\right(CN{)}_6]$
• C. $ZnC{l}_2$
• D. $N{a}_{2}S{O}_4$

Answer 1

The correct option is B

$K_4\left[Fe\right(CN{)}_6]$

Positively charged colloidal particles can be coagulated by negatively charged anions, higher the charge on anion, lower the concentration required I.e, $\left[Fe\right(CN{)}_6{]}^{-4}$