`HgI_(2)darr+2HI to K_(2)[HgI_(4)]`

Options

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

Answer

To analyze the reaction \( \text{HgI}_2 + 2 \text{HI} \rightarrow \text{K}_2[\text{HgI}_4] \), we need to identify the type of reaction taking place. Here’s a step-by-step breakdown:

### Step 1: Identify the Reactants and Products
- The reactants are \( \text{HgI}_2 \) (mercury(II) iodide) and \( \text{HI} \) (hydroiodic acid).
- The product is \( \text{K}_2[\text{HgI}_4] \) (potassium tetraiodomercurate(II)).

### Step 2: Analyze the State of Reactants
- \( \text{HgI}_2 \) is a solid precipitate, as indicated by the downward arrow in the reaction.
- \( \text{HI} \) is a gas or aqueous solution.

### Step 3: Determine the Reaction Type
- In this reaction, \( \text{HgI}_2 \) is dissolving in the presence of \( \text{HI} \) to form a complex ion \( \text{K}_2[\text{HgI}_4] \).
- Since \( \text{HgI}_2 \) is a precipitate that is being dissolved to form a soluble complex, this indicates a dissolution process.

### Step 4: Conclusion
- The reaction can be classified as a **precipitate dissolution reaction** because the solid precipitate \( \text{HgI}_2 \) is dissolving to form a soluble product.

### Final Answer
The type of reaction is a **precipitate dissolution reaction**.

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