Question

The coagulating power of an electrolyte for arsenious sulphide decreases in the order:

• A. $N{{a}^{+}}>A{{l}^{3+}}>B{{a}^{2+}}$
• B. $PO_{4}^{3-}>SO_{4}^{2-}>C{{l}^{-}}$
• C. $Cl>SO_{4}^{2-}>PO_{4}^{3-}$
• D. $A{{l}^{3+}}>B{{a}^{2+}}>N{{a}^{+}}$

Answer 1

Answer: (D)

$A{{l}^{3+}}>B{{a}^{2+}}>N{{a}^{+}}$

Answer 2

According to Hardy Schuiz rule, the coagulating power of electrolyte increases with charge on ion. $\because$ $\text{A}{{\text{s}}_{\text{2}}}{{\text{S}}_{\text{3}}}$ is negatively charged colloid and so it will be coagulated by cations. $\therefore$ Correct order of coagulating power for $\text{A}{{\text{s}}_{\text{2}}}{{\text{S}}_{\text{3}}}$ is $A{{l}^{3+}}>B{{a}^{2+}}>N{{a}^{+}}$