Which ion will give colour in the aqueous solution ?

Options

A. `Ti^(3+)`
B. `Cu^(2+)`
C. `Cu^+`
D. Both a and b

Answer

To determine which ion will give color in an aqueous solution, we need to analyze the electronic configurations of the given ions: Ti³⁺, Cu²⁺, Cu⁺, and both A and B. The presence of unpaired electrons in the d-orbitals of these ions is what causes them to exhibit color.

### Step-by-Step Solution:

1. **Identify the Ions and Their Electronic Configurations**:
- **Titanium (Ti)** has an atomic number of 22. Its electronic configuration is:
\[ \text{Ti: } [\text{Ar}] 3d^2 4s^2 \]
- **Copper (Cu)** has an atomic number of 29. Its electronic configuration is:
\[ \text{Cu: } [\text{Ar}] 3d^{10} 4s^1 \]

2. **Determine the Configuration of Ti³⁺**:
- For Ti³⁺, we remove three electrons:
- First, remove the two electrons from the 4s orbital.
- Then, remove one electron from the 3d orbital.
- The electronic configuration for Ti³⁺ becomes:
\[ \text{Ti}^{3+}: [\text{Ar}] 3d^1 4s^0 \]
- **Unpaired Electrons**: There is **1 unpaired electron** in Ti³⁺.

3. **Determine the Configuration of Cu²⁺**:
- For Cu²⁺, we remove two electrons:
- One from the 4s orbital and one from the 3d orbital.
- The electronic configuration for Cu²⁺ becomes:
\[ \text{Cu}^{2+}: [\text{Ar}] 3d^9 4s^0 \]
- **Unpaired Electrons**: There is **1 unpaired electron** in Cu²⁺.

4. **Determine the Configuration of Cu⁺**:
- For Cu⁺, we remove one electron from the 4s orbital:
- The electronic configuration for Cu⁺ becomes:
\[ \text{Cu}^+: [\text{Ar}] 3d^{10} 4s^0 \]
- **Unpaired Electrons**: There are **no unpaired electrons** in Cu⁺.

5. **Conclusion**:
- Ions that exhibit color in aqueous solutions must have unpaired electrons.
- From our analysis:
- Ti³⁺ has 1 unpaired electron (shows color).
- Cu²⁺ has 1 unpaired electron (shows color).
- Cu⁺ has no unpaired electrons (does not show color).
- Therefore, the ions that give color in aqueous solution are **Ti³⁺ and Cu²⁺**.

### Final Answer:
The correct option is **both A (Ti³⁺) and B (Cu²⁺)** show color in aqueous solution.

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