When a solid `KCI` is added to a saturated solution of `AgCI "in" H_(2)O`,

Options

A. Nothing happens.
B. Solubility of `AgCI` decreases.
C. Solubility of `AgCI` increases.
D. Solubility product of `AgCI` increases.

Explanation

To solve the problem of what happens when solid KCl is added to a saturated solution of AgCl in water, we can follow these steps:

### Step 1: Understand the Dissociation of AgCl
AgCl is a sparingly soluble salt that dissociates in water according to the following equilibrium:
\[ \text{AgCl (s)} \rightleftharpoons \text{Ag}^+ (aq) + \text{Cl}^- (aq) \]

### Step 2: Identify the Effect of Adding KCl
When KCl is added to the solution, it dissociates completely into its ions:
\[ \text{KCl (s)} \rightarrow \text{K}^+ (aq) + \text{Cl}^- (aq) \]

### Step 3: Recognize the Common Ion Effect
The addition of KCl increases the concentration of Cl⁻ ions in the solution. Since Cl⁻ is a common ion in the equilibrium of AgCl, this will affect the solubility of AgCl.

### Step 4: Apply Le Chatelier's Principle
According to Le Chatelier's principle, if a system at equilibrium is disturbed by changing the conditions, the system will shift in a direction that counteracts the change. In this case, the increase in Cl⁻ concentration will shift the equilibrium to the left:
\[ \text{Ag}^+ (aq) + \text{Cl}^- (aq) \rightleftharpoons \text{AgCl (s)} \]

### Step 5: Conclusion on Solubility
As a result of the shift in equilibrium to the left, the solubility of AgCl decreases. This means that less AgCl will dissolve in the solution because the common ion (Cl⁻) suppresses the dissociation of AgCl.

### Step 6: Ksp Consideration
The solubility product constant (Ksp) for AgCl is given by:
\[ Ksp = [\text{Ag}^+][\text{Cl}^-] \]
With the addition of KCl, the concentration of Cl⁻ increases, which means that the concentration of Ag⁺ must decrease to maintain the Ksp value. Therefore, the solubility product does not increase; it effectively decreases as the solubility of AgCl decreases.

### Final Answer
The solubility of AgCl decreases when solid KCl is added to a saturated solution of AgCl in water.

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