Assertion: `Ti^(3+)` salts are coloured whereas `Ti^(4+)` salts are white. Reason: `Ti^(3+)` is less stable than `Ti^(4+)`

Options

A. If both Assertion & Reason are true and the reason is the correct explanation of the assertion, then mark (1)
B. If both Assertion & Reason are true but the reason is not the correct explanation of the assertion, then mark (2)
C. If Assertion is true statement but Reason is false, then mark (3)
D. If both Assertion and Reason are false statements, then mark (4)

Answer

To solve the question, we will analyze both the assertion and the reason provided in the statement.

### Step 1: Analyze the Assertion
The assertion states that `Ti^(3+)` salts are colored while `Ti^(4+)` salts are white.

- **Explanation**: The color of transition metal salts is generally due to the presence of unpaired electrons in their d-orbitals. Transition metals can absorb certain wavelengths of light, and the color observed is the complementary color of the light absorbed.

### Step 2: Determine the Electronic Configuration
Now, let's determine the electronic configurations of `Ti^(3+)` and `Ti^(4+)`.

- **Titanium (Ti)** has the atomic number 22, and its ground state electronic configuration is:
\[ \text{Ti: } [Ar] 3d^2 4s^2 \]

- **For `Ti^(3+)`**: Removing three electrons (two from 4s and one from 3d):
\[ \text{Ti}^{3+}: [Ar] 3d^1 \]
This configuration has one unpaired electron.

- **For `Ti^(4+)`**: Removing four electrons (two from 4s and two from 3d):
\[ \text{Ti}^{4+}: [Ar] 3d^0 \]
This configuration has no unpaired electrons.

### Step 3: Conclusion on Colors
- Since `Ti^(3+)` has one unpaired electron, it is colored.
- Since `Ti^(4+)` has no unpaired electrons, it is colorless (white).

### Step 4: Analyze the Reason
The reason states that `Ti^(3+)` is less stable than `Ti^(4+)`.

- **Explanation**: The stability of oxidation states in transition metals can be attributed to their ability to achieve a stable electronic configuration. The `Ti^(4+)` state is more stable because it achieves a noble gas configuration (octet). The `Ti^(3+)` state is less stable due to having an unpaired electron in its d-orbital.

### Step 5: Evaluate the Relationship Between Assertion and Reason
- Both the assertion and reason are correct.
- However, the reason provided does not directly explain why `Ti^(3+)` salts are colored and `Ti^(4+)` salts are white. The color is due to the presence of unpaired electrons, not merely the stability of the oxidation states.

### Final Answer
The correct option is:
- **Both assertion and reason are correct, but the reason is not the correct explanation of the assertion.**