A : All the oxides of boron family with the general formula `M_(2) O_(3)` are basic .
R : From `B_(2) O_(3)` to `Tl_(2) O_(3)` basic character decreases .

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 analyze the assertion and reason provided in the question, let's break it down step by step.

### Step 1: Understanding the Assertion
- **Assertion (A)** states that all the oxides of the boron family with the general formula \( M_2O_3 \) are basic.
- The boron family consists of elements such as Boron (B), Aluminium (Al), Gallium (Ga), Indium (In), and Thallium (Tl).
- The general formula \( M_2O_3 \) indicates that these oxides are formed by these elements reacting with oxygen.

### Step 2: Evaluating the Basicity of Oxides
- Basicity refers to the ability of an oxide to react with acids to form salts and water.
- In the case of the boron family, as we move from Boron to Thallium, the metallic character increases, which generally leads to an increase in basicity.
- Boron oxide (\( B_2O_3 \)) is amphoteric (can act as both an acid and a base), while Aluminium oxide (\( Al_2O_3 \)) is more basic, and the basicity continues to increase down the group.

### Step 3: Understanding the Reason
- **Reason (R)** states that from \( B_2O_3 \) to \( Tl_2O_3 \), the basic character decreases.
- This statement is incorrect because, as we move down the group from Boron to Thallium, the basic character actually increases due to the increasing metallic character.

### Step 4: Conclusion
- The assertion is correct: all the oxides of the boron family with the general formula \( M_2O_3 \) are basic.
- The reason is incorrect: the basic character does not decrease from \( B_2O_3 \) to \( Tl_2O_3 \); it actually increases.

### Final Answer
- The assertion (A) is true, and the reason (R) is false. Therefore, the correct conclusion is that the assertion is correct, but the reason is not.

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