Which of the following mixtures of ions in solution can be separted by using `NH_(3)` solution?

Options

A. `Hg_(2)^(2+) and Ag^(+)`
B. `Bi^(3+) and Cu^(2+)`
C. `Ag^(+) and Pb^(2+)`
D. `Cu^(2+) and Cd^(2+)`

Answer

To determine which mixtures of ions in solution can be separated by using NH₃ solution, we will analyze each option based on the solubility of the ions in ammonia.

### Step-by-Step Solution:

1. **Option 1: Hg²⁺ and Ag⁺**
- **Analysis**:
- Ag⁺ forms a soluble complex with NH₃, specifically [Ag(NH₃)₂]⁺.
- Hg²⁺ reacts with NH₃ to form a black precipitate of Hg(NH₂)₂.
- **Conclusion**: These ions can be separated using NH₃ solution.

2. **Option 2: Bi³⁺ and Cu²⁺**
- **Analysis**:
- Bi³⁺ is generally insoluble in NH₃, forming a precipitate.
- Cu²⁺ forms a soluble complex with NH₃, specifically [Cu(NH₃)₄]²⁺.
- **Conclusion**: These ions can also be separated using NH₃ solution.

3. **Option 3: Ag⁺ and Pb²⁺**
- **Analysis**:
- Ag⁺ is soluble in NH₃, forming a complex [Ag(NH₃)₂]⁺.
- Pb²⁺ does not form a soluble complex with NH₃ and remains in solution.
- **Conclusion**: These ions can be separated using NH₃ solution.

4. **Option 4: Cu²⁺ and Cd²⁺**
- **Analysis**:
- Cu²⁺ forms a soluble complex with NH₃, [Cu(NH₃)₄]²⁺.
- Cd²⁺ does not form a complex with NH₃ and is typically precipitated as CdS when H₂S is passed through the solution.
- **Conclusion**: These ions cannot be separated using NH₃ solution; they require KCN for separation.

### Final Answer:
The mixtures of ions that can be separated using NH₃ solution are:
- Option 1: Hg²⁺ and Ag⁺
- Option 2: Bi³⁺ and Cu²⁺
- Option 3: Ag⁺ and Pb²⁺