Which factor would increase the solubility of AgCl?

Which factor would increase the solubility of AgCl?

• A. Increasing temperature
• B. Adding a common ion (Cl-)
• C. Decreasing ionic strength
• D. Lowering temperature

Answer: (C)

Solubility of a sparingly soluble salt like AgCl is governed by the dissolution equilibrium AgCl(s) ⇌ Ag+ + Cl−, with the solubility product Ksp = a_Ag+ · a_Cl−. Temperature changes influence this system because the dissolution is typically endothermic: increasing temperature supplies energy that helps break the lattice and hydrate the ions, shifting the equilibrium toward more dissolved ions and raising solubility. Adding a common ion (Cl−) drives the equilibrium to the left, lowering solubility. Lowering temperature generally reduces solubility for most salts because the dissolution process is not favored at lower heat input. Ionic strength affects solubility through activity coefficients in a more subtle way, and it’s not the primary knob here. So the factor that would most reliably increase the solubility of AgCl is increasing temperature.

Solubility of a sparingly soluble salt like AgCl is governed by the dissolution equilibrium AgCl(s) ⇌ Ag+ + Cl−, with the solubility product Ksp = a_Ag+ · a_Cl−. Temperature changes influence this system because the dissolution is typically endothermic: increasing temperature supplies energy that helps break the lattice and hydrate the ions, shifting the equilibrium toward more dissolved ions and raising solubility.

Adding a common ion (Cl−) drives the equilibrium to the left, lowering solubility. Lowering temperature generally reduces solubility for most salts because the dissolution process is not favored at lower heat input. Ionic strength affects solubility through activity coefficients in a more subtle way, and it’s not the primary knob here.

So the factor that would most reliably increase the solubility of AgCl is increasing temperature.