Which of the following ions are paramagnetic in character?

Options

A. `Zn^(+2)`
B. `Cu^(+)`
C. `Ni^(2+)`
D. `Ag^(+)`

Explanation

To determine which of the given ions are paramagnetic, we need to analyze the electron configurations of each ion and check for the presence of unpaired electrons. Paramagnetic ions contain unpaired electrons, while diamagnetic ions have all electrons paired.

### Step-by-Step Solution:

1. **Understand Paramagnetism**:
- Paramagnetic substances have unpaired electrons in their electron configuration. This means that if an ion has one or more unpaired electrons, it will exhibit paramagnetic behavior.

2. **Identify the Ions**:
- The ions we need to analyze are Zinc (Zn²⁺), Copper (Cu⁺), Nickel (Ni²⁺), and Silver (Ag).

3. **Find Electron Configurations**:
- **Zinc (Zn²⁺)**:
- Atomic number of Zn = 30
- Electron configuration: [Ar] 3d¹⁰ 4s²
- For Zn²⁺: Remove 2 electrons from 4s, giving [Ar] 3d¹⁰.
- **Unpaired Electrons**: 0 (fully filled d-orbital).

- **Copper (Cu⁺)**:
- Atomic number of Cu = 29
- Electron configuration: [Ar] 3d¹⁰ 4s¹
- For Cu⁺: Remove 1 electron from 4s, giving [Ar] 3d¹⁰.
- **Unpaired Electrons**: 0 (fully filled d-orbital).

- **Nickel (Ni²⁺)**:
- Atomic number of Ni = 28
- Electron configuration: [Ar] 3d⁸ 4s²
- For Ni²⁺: Remove 2 electrons from 4s, giving [Ar] 3d⁸.
- **Unpaired Electrons**: 2 (the 3d subshell has 8 electrons, which means there are unpaired electrons).

- **Silver (Ag)**:
- Atomic number of Ag = 47
- Electron configuration: [Kr] 4d¹⁰ 5s¹
- For Ag: Remove 1 electron from 5s, giving [Kr] 4d¹⁰.
- **Unpaired Electrons**: 0 (fully filled d-orbital).

4. **Conclusion**:
- From the analysis, only Nickel (Ni²⁺) has unpaired electrons and is therefore paramagnetic.
- The other ions (Zn²⁺, Cu⁺, and Ag) are diamagnetic as they have no unpaired electrons.

### Final Answer:
- The only ion that is paramagnetic is **Ni²⁺**.