Chemistry · Chemical Equilibrium
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The solubility of AgCl decreases by adding:
- A
H2SO4
- B
HF
- C
NaCl
- D
H2O
The correct answer is NaCl because it provides Cl- ions, which are a common ion with AgCl (AgCl is composed of Ag+ and Cl- ions). The presence of the common ion (Cl-) shifts the equilibrium of the dissolution reaction of AgCl to the left, thereby decreasing its solubility according to Le Chatelier's principle.
In contrast, H2SO4 and HF do not provide a common ion that interacts with AgCl, so they do not significantly influence its solubility. H2O merely dilutes the solution without affecting the ion concentration needed to alter AgCl solubility.
H2SO4 is a strong acid that dissociates in water to produce H+ ions and SO42- ions. While it increases the acidity of the solution, it does not directly contribute a common ion to decrease the solubility of AgCl.
HF is a weak acid that partially dissociates in solution, producing H+ ions and F- ions. However, it does not provide a common ion with AgCl, and thus does not significantly affect its solubility.
NaCl dissociates in solution to produce Na+ and Cl- ions. The addition of Cl- ions introduces a common ion to the solution, which decreases the solubility of AgCl due to the common ion effect.
Adding H2O dilutes the solution but does not provide any ions that would affect the solubility of AgCl. It does not decrease the solubility, making it an ineffective option.
Tagged under Chemistry · Chemical Equilibrium