Consider the following salts: `NaCl, HgCl_2, Hg_2Cl_2, CuCl_2 and AgCl`. Identify the correct set of insoluble salts in water

Options

A. `Hg_2Cl_2, CuCl, AgCl`
B. `HgCl_2, CuCl , AgCl`
C. `Hg_2 Cl_2, CuCl_2 ,AgCl`
D. `Hg_2 Cl_2, CuCl , NaCl`

Explanation

To determine the correct set of insoluble salts in water from the given list of salts (NaCl, HgCl2, Hg2Cl2, CuCl2, and AgCl), we will analyze the solubility of each salt.

### Step 1: Analyze the solubility of NaCl
- **NaCl (Sodium Chloride)**: Sodium salts are generally soluble in water. Therefore, NaCl is soluble in water.

### Step 2: Analyze the solubility of HgCl2
- **HgCl2 (Mercury(II) Chloride)**: Mercury(II) chloride is soluble in water. It forms a clear solution when dissolved.

### Step 3: Analyze the solubility of Hg2Cl2
- **Hg2Cl2 (Mercury(I) Chloride)**: Mercury(I) chloride, also known as calomel, is insoluble in water. It does not dissolve and typically appears as a white precipitate.

### Step 4: Analyze the solubility of CuCl2
- **CuCl2 (Copper(II) Chloride)**: Copper(II) chloride is soluble in water. It dissolves to form a blue solution.

### Step 5: Analyze the solubility of AgCl
- **AgCl (Silver Chloride)**: Silver chloride is insoluble in water. It forms a white precipitate when mixed with water.

### Conclusion
From the analysis, the salts that are insoluble in water are:
- Hg2Cl2 (Mercury(I) Chloride)
- AgCl (Silver Chloride)

Thus, the correct set of insoluble salts in water is **{Hg2Cl2, AgCl}**.