When mercury (II) chloride is treated with excess of stannous chloride, the products obtained are :

Options

A. liquid Hg and `SnCl_(4)`
B. `Hg_(2)Cl_(2) and SnCl_(4)`
C. `Hg_(2)Cl_(2) and [SnCl_(4)]^(2-)`
D. liquid Hg and `[SnCl_(4)]^(2-)`

Answer

To solve the question regarding the reaction between mercury (II) chloride (HgCl2) and excess stannous chloride (SnCl2), we can break down the process step-by-step.

### Step-by-Step Solution:

1. **Identify the Reactants**:
The reactants in this reaction are mercury (II) chloride (HgCl2) and stannous chloride (SnCl2).

2. **Understand the Reaction**:
When HgCl2 is treated with SnCl2, a redox reaction occurs. In this reaction, HgCl2 acts as an oxidizing agent and SnCl2 acts as a reducing agent.

3. **Oxidation and Reduction**:
- SnCl2 is oxidized to stannic chloride (SnCl4).
- HgCl2 is reduced to mercurous chloride (Hg2Cl2).

4. **Write the Balanced Reaction**:
The balanced chemical equation for the reaction can be written as follows:
\[ \text{HgCl}_2 + \text{SnCl}_2 \rightarrow \text{Hg}_2\text{Cl}_2 + \text{SnCl}_4 \]

5. **Consider Excess Stannous Chloride**:
Since we have excess SnCl2, it can further reduce the mercurous chloride (Hg2Cl2) to metallic mercury (Hg):
\[ \text{Hg}_2\text{Cl}_2 + 2 \text{SnCl}_2 \rightarrow 2 \text{Hg} + 2 \text{SnCl}_4 \]

6. **Final Products**:
The final products of the reaction when excess SnCl2 is used are:
- Metallic mercury (Hg)
- Stannic chloride (SnCl4)

### Conclusion:
The products obtained when mercury (II) chloride is treated with excess stannous chloride are metallic mercury (Hg) and stannic chloride (SnCl4).