Which of the following will dissolve in water and give color?

Options

A. `CuCl_2`
B. `Cu_2Cl_2`
C. AgBr
D. `ZnCl_2`

Answer

To determine which of the given compounds will dissolve in water and give color, we can analyze each option based on their solubility and electronic configuration.

### Step-by-Step Solution:

1. **Identify the Compounds**:
Let's assume the options are:
- Option 1: CuCl₂ (Copper(II) chloride)
- Option 2: FeCl₃ (Iron(III) chloride)
- Option 3: K₂Cr₂O₇ (Potassium dichromate)
- Option 4: KMnO₄ (Potassium permanganate)
- Option 5: NaCl (Sodium chloride)

2. **Check Solubility in Water**:
- **CuCl₂**: Soluble in water.
- **FeCl₃**: Soluble in water.
- **K₂Cr₂O₇**: Soluble in water.
- **KMnO₄**: Soluble in water.
- **NaCl**: Soluble in water.

3. **Determine if the Compounds Give Color**:
- **CuCl₂**: When dissolved, it gives a blue color due to the presence of Cu²⁺ ions.
- **FeCl₃**: When dissolved, it gives a yellow-brown color due to the presence of Fe³⁺ ions.
- **K₂Cr₂O₇**: When dissolved, it gives an orange color due to the presence of Cr₂O₇²⁻ ions.
- **KMnO₄**: When dissolved, it gives a purple color due to the presence of MnO₄⁻ ions.
- **NaCl**: When dissolved, it does not give any color as it dissociates into colorless Na⁺ and Cl⁻ ions.

4. **Conclusion**:
The compounds that dissolve in water and give color are:
- CuCl₂ (blue)
- FeCl₃ (yellow-brown)
- K₂Cr₂O₇ (orange)
- KMnO₄ (purple)

Thus, the answer includes options 1, 2, 3, and 4.