Which one of the following forms a basic oxide?

Options

A. B
B. Tl
C. Al
D. Ga

Answer

To determine which element among boron, aluminium, gallium, and thallium forms a basic oxide, we can follow these steps:

### Step 1: Understand the Oxide Types
- **Basic Oxides**: These are oxides that react with acids to form salt and water. They are typically formed by metals.
- **Acidic Oxides**: These are oxides that react with bases to form salt and water. They are usually formed by non-metals.
- **Amphoteric Oxides**: These can react with both acids and bases, showing characteristics of both.

### Step 2: Analyze the Elements
- **Boron (B)**: It is a non-metal and typically forms acidic oxides (e.g., B2O3).
- **Aluminium (Al)**: It is a metal but forms amphoteric oxides (e.g., Al2O3), which can react with both acids and bases.
- **Gallium (Ga)**: Like aluminium, gallium is also a metal and forms amphoteric oxides (e.g., Ga2O3).
- **Thallium (Tl)**: This is a heavier metal that tends to exhibit more metallic character and forms basic oxides (e.g., Tl2O3).

### Step 3: Determine the Correct Answer
Since we are looking for the element that forms a basic oxide, we can conclude that thallium (Tl) is the correct answer. It forms basic oxides due to its metallic character.

### Conclusion
The element that forms a basic oxide among the given options is **Thallium (Tl)**.

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