Question

The correct order of increasing solubility of AgCl in $\left(\mathrm{A}\right)$ Water $\left(\mathrm{B}\right)$ $0.1\mathrm{M}$ $\mathrm{NaCl}$ $\left(\mathrm{C}\right)$ $0.1\mathrm{M}$ ${\mathrm{BaCl}}_2$$\left(\mathrm{D}\right)$ $0.1\mathrm{M}$ ${\mathrm{NH}}_3$

• A. A$<$B$<$C$<$D
• B. B$<$C$<$A$<$D
• C. C$<$B$<$D$<$A
• D. C$<$B$<$A$<$D

Answer 1

The correct option is D

C$<$B$<$A$<$D

The explanation for the correct option:

Option (D): C$<$B$<$A$<$D

1. Solubility refers to a substance's ability to dissolve in a solvent.
2. We will apply the concept of the common ion effect to determine the rising solubility of a solution, which asserts that when a solution is added to a soluble substance, the solubility will decrease if common ions are present.
3. Here solubility is proportional to the concentration of chloride ions and silver ions
4. $\mathrm{NaCl}$ dissociate into one chloride ion hence the solubility will be slightly more than ${\mathrm{BaCl}}_2$
5. Because ${\mathrm{BaCl}}_2$ dissociate into two chloride ions when $\mathrm{AgCl}$ is dissolved in it, the decrease will be greater.
6. When $\mathrm{AgCl}$ is dissolved in ${\mathrm{NH}}_3$, it forms a complex with ammonia,${\left[\mathrm{Ag}{\left({\mathrm{NH}}_3\right)}_2\right]}^{+}$ which makes it very soluble in ammonia.
7. $\mathrm{AgCl}$ will be soluble in water as well, but not as much as ammonia, because oxygen is more electronegative than nitrogen, making ammonia less polar than water.
8. Hence, it is the correct option

The explanation for the incorrect options:

Option (A): A$<$B$<$C$<$D

1. Solubility is affected by the presence of a common ion in a solution. The more the common ion present, the lesser the solubility.
2. Here, ${\mathrm{BaCl}}_2$ gives two chloride ions, Hence the solubility will be minimum in ${\mathrm{BaCl}}_2$
3. Hence, it is an incorrect option.

Option (B): B$<$C$<$A$<$D

1. Solubility is affected by the presence of a common ion in a solution. The more the common ion present, the lesser the solubility.
2. Both $\mathrm{NaCl}$ and ${\mathrm{BaCl}}_2$ contains chloride ion but the number of chloride ions present in ${\mathrm{BaCl}}_2$ is more as compared to $\mathrm{NaCl}$, hence it will least soluble in ${\mathrm{BaCl}}_2$
3. Hence, it is an incorrect option.

Option (C): C$<$B$<$D$<$A

1. $\mathrm{AgCl}$ is soluble in both water and ${\mathrm{NH}}_3$ solution due to the absence of common ions.
2. But it is more soluble in ${\mathrm{NH}}_3$it forms a complex${\left[\mathrm{Ag}{\left({\mathrm{NH}}_3\right)}_2\right]}^{+}$, which makes it very soluble in ammonia.
3. Hence, it is an incorrect option.

Therefore, the correct order of increasing solubility of AgCl is C$<$B$<$A$<$D, option (D) is the correct answer.