Question

The flocculating power of the given ions for the specified colloidal sols will be such that

• A.

  Arsenic sulphoid sol	Ferric hydroxide sol
  ${\left(\left[Fe{\left(CN\right)}_6\right]\right)}^{4-}>P{O}_4^{3-}>S{O}_4^{2-}>C{l}^{-}$	$A{l}^{3+}>B{a}^{2+}>N{a}^{+}$

• B.

  Arsenic sulphoid sol	Ferric hydroxide sol
  $A{l}^{3+}>B{a}^{2+}>N{a}^{+}$	${\left(\left[Fe{\left(CN\right)}_6\right]\right)}^{4-}>P{O}_4^{3-}>S{O}_4^{2-}>C{l}^{-}$

• C.

  Arsenic sulphoid sol	Ferric hydroxide sol
  $N{a}^{+}>B{a}^{2+}>A{l}^{3+}$	$C{l}^{-}>S{O}_4^{2-}>P{O}_4^{3-}>{\left(\left[Fe{\left(CN\right)}_6\right]\right)}^{4-}$

• D.

  Arsenic sulphoid sol	Ferric hydroxide sol
  $C{l}^{-}>S{O}_4^{2-}>P{O}_4^{3-}>{\left(\left[Fe{\left(CN\right)}_6\right]\right)}^{4-}$	$N{a}^{+}>B{a}^{2+}>A{l}^{3+}$

Answer 1

Answer: (B)

Coagulation power depends on nature of charge and amount of charge
Coagulation power $\propto$ charge on ion of electrolyte
As Arsenic sulphoid sol is negatively charged so for it cations will cause precipitation of ions and the order is $A{l}^{3+}>B{a}^{2+}>N{a}^{+}$
As Ferric hydroxide sol is positively charged so for it anions will cause precipitation of ions and the order is
${\left[Fe(CN{)}_6\right]}^{4-}>P{O}_4^{3-}>S{O}_4^{2-}>C{l}^{-}$