`Hg(NO_(3))_(2)+NH_(3)("soln.")toMgO*HgNH_(2)NO_(3)darr`

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 given in the question, we need to identify the type of reaction occurring between the reactants: Hg(NO₃)₂ and NH₃ (in solution).

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactants in the equation are Mercury(II) nitrate (Hg(NO₃)₂) and Ammonia (NH₃) in solution.

2. **Analyze the Reaction**:
- When Hg(NO₃)₂ reacts with NH₃, it forms a complex compound, which is Mercury(I) amide nitrate (HgNH₂NO₃) and may also involve the formation of some precipitate.

3. **Determine the Type of Reaction**:
- We need to classify the reaction based on the presence or absence of precipitates before and after the reaction.
- In this case, there is no precipitate on the reactant side (before the reaction) since we are starting with soluble compounds.
- After the reaction, a precipitate is formed (HgNH₂NO₃), indicating that a new solid compound has been created.

4. **Conclusion**:
- Since there was no precipitate present initially and a precipitate is formed after the reaction, this is classified as a **precipitate formation reaction**.

### Final Answer:
The reaction between Hg(NO₃)₂ and NH₃ in solution results in the formation of a precipitate, making it a **precipitate formation reaction**.

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