Which is pure basic oxide

Options

A. `Al_(2)O_(3)`
B. `Tl_(2)O_(3)`
C. `B_(2)O_(3)`
D. `N_(2)O`

Explanation

To determine which of the given oxides is a pure basic oxide, we need to analyze each option based on their chemical properties.

### Step-by-Step Solution:

1. **Identify the Oxides**: The options given are:
- Aluminium oxide (Al₂O₃)
- Thallium oxide (Tl₂O₃)
- Boron oxide (B₂O₃)
- Dinitrogen oxide (N₂O)

2. **Understand Basic Oxides**: Basic oxides are typically formed by metals and can react with acids to form salts and water. They are generally ionic in nature and can accept protons (H⁺ ions).

3. **Analyze Aluminium Oxide (Al₂O₃)**:
- Aluminium oxide is classified as an **amphoteric oxide**. This means it can act as both an acid and a base depending on the conditions. Therefore, it is not a pure basic oxide.

4. **Analyze Thallium Oxide (Tl₂O₃)**:
- Thallium oxide is formed from thallium, which is a heavier metal in the group. As we move down the group in the periodic table, the basicity of oxides generally increases. Thallium oxide is considered a **basic oxide** because it can react with acids to form salts.

5. **Analyze Boron Oxide (B₂O₃)**:
- Boron oxide is known to be an **acidic oxide**. It can react with bases but not with acids in the same way basic oxides do. Therefore, it is not a pure basic oxide.

6. **Analyze Dinitrogen Oxide (N₂O)**:
- Dinitrogen oxide is a neutral oxide and does not exhibit basic properties. It does not react with acids or bases in a manner typical of basic oxides.

7. **Conclusion**: Among the options provided, **Thallium oxide (Tl₂O₃)** is the only pure basic oxide.

### Final Answer:
The pure basic oxide among the options is **Thallium oxide (Tl₂O₃)**.

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