Coloured ion among the following is

Options

A. `Zn^(2+)`
B. `Mn^(2+)`
C. `Cu^(1+)`
D. `Ti^(4+)`

Answer

To determine which of the given ions is colored, we need to analyze their electronic configurations and check for the presence of unpaired d electrons. Colored ions typically arise from transition metals that have unpaired d electrons, as these electrons can transition between different energy levels when exposed to light, leading to the absorption of certain wavelengths and the appearance of color.

### Step-by-step Solution:

1. **Identify the Ions**: The ions provided are Zn²⁺, Mg²⁺, Cu⁺, and Ti⁴⁺.

2. **Write the Electron Configurations**:
- **Zn²⁺**: The atomic number of Zinc (Zn) is 30. The electron configuration is:
- Zn: [Ar] 3d¹⁰ 4s²
- Zn²⁺: [Ar] 3d¹⁰ (loses 2 electrons from 4s)
- **Mg²⁺**: The atomic number of Magnesium (Mg) is 12. The electron configuration is:
- Mg: [Ne] 3s²
- Mg²⁺: [Ne] (loses 2 electrons from 3s)
- **Cu⁺**: The atomic number of Copper (Cu) is 29. The electron configuration is:
- Cu: [Ar] 3d¹⁰ 4s¹
- Cu⁺: [Ar] 3d¹⁰ (loses 1 electron from 4s)
- **Ti⁴⁺**: The atomic number of Titanium (Ti) is 22. The electron configuration is:
- Ti: [Ar] 3d² 4s²
- Ti⁴⁺: [Ar] (loses all 4 electrons from 4s and 3d)

3. **Check for Unpaired Electrons**:
- **Zn²⁺**: 3d¹⁰ → All electrons are paired (no color).
- **Mg²⁺**: [Ne] → No d electrons (no color).
- **Cu⁺**: 3d¹⁰ → All electrons are paired (no color).
- **Ti⁴⁺**: [Ar] → No d electrons (no color).

4. **Conclusion**: None of the ions have unpaired d electrons. However, if we were to consider a related ion, Mn²⁺ (which is not listed), it would have unpaired electrons and thus would be colored. Among the provided options, none are colored ions.

### Final Answer:
None of the given ions (Zn²⁺, Mg²⁺, Cu⁺, Ti⁴⁺) are colored.