Question

Let the solubilities of $AgCl$ in $H_{2}O$, and $0.01MCaC{l}_2,0.01MNaCl$, and $0.05MAgN{O}_3$ be $S_1,S_2,S_3,S_4$, respectively. What is the correct relationship between these quantities

• A. $S_2>S_2>S_3>S_4$
• B. $S_1>S_2=S_3>S_4$
• C. $S_1>S_3>S_2>S_4$
• D. $S_4>S_2>S_3>S_1$

Answer 1

Answer: (C)

i. $AgCl+H_{2}O⟶A{g}^{\oplus }(aq)+C{l}^{\ominus }(aq)\dots S_1$
ii. $AgCl$ in $0.01MCaC{l}_2,\dots S_2$
Concentration of $C{l}^{\Theta }=2\times 0.01=0.02M$
iii. $AgCl$ in $0.01MNaCl\dots S_3$
Concentration of $C{l}^{\ominus }=0.01M$
iv. $AgCl$ is $0.05M,AgN{O}_3,\dots S_4$
Concentration of $A{g}^{\oplus }=0.05$
Since both $C{l}^{\ominus }$ ion and $A{g}^{\oplus }$ ions acts as common ion. So larger the concentration of $A{g}^{\oplus }$ or $C{l}^{\ominus }$ ions, more is the suppression of ionization of $AgCl$ and hence less will be solubility of $AgCl$
$\therefore$ Solubility order
$S_1>S_3>S_2>S_4$