`AgCldarr+2KCN to K[Ag(CN)_(2)]+KCl`

Options

A. For precipitate formation reaction
B. For precipitate dissolution reaction
C. For precipitate exchange reaction
D. For no reaction

Answer

To analyze the given reaction \( \text{AgCl} + 2\text{KCN} \rightarrow \text{K[Ag(CN)}_2] + \text{KCl} \), we need to determine the type of reaction it represents. Here’s a step-by-step breakdown of the solution:

### Step 1: Identify the Reactants and Products
- **Reactants**: Silver chloride (AgCl) and potassium cyanide (KCN).
- **Products**: Potassium dicyanoargentate (K[Ag(CN)₂]) and potassium chloride (KCl).

### Step 2: Determine the Nature of AgCl
- AgCl is known to be a precipitate, which means it is insoluble in water and will appear as a solid in the reaction mixture.

### Step 3: Analyze the Products
- The product K[Ag(CN)₂] is a complex ion that is soluble in water. KCl is also a soluble salt.

### Step 4: Compare Precipitate Presence in Reactants and Products
- In the reactants, we have AgCl as a precipitate.
- In the products, both K[Ag(CN)₂] and KCl are soluble, indicating that there is no precipitate formed in the products.

### Step 5: Conclusion
- Since we start with a precipitate (AgCl) in the reactants and end with no precipitate in the products, this indicates that the precipitate has dissolved during the reaction. Therefore, this reaction is classified as a **precipitate dissolution reaction**.

### Final Answer
The reaction \( \text{AgCl} + 2\text{KCN} \rightarrow \text{K[Ag(CN)}_2] + \text{KCl} \) is a **precipitate dissolution reaction**.

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