Among the group 13 the only element which is non -metal

Options

A. B
B. Al
C. Ga
D. ln

Answer

To solve the question of identifying the only non-metal in group 13, we will follow these steps:

### Step-by-Step Solution:

1. **Identify Group 13 Elements**:
- The elements in group 13 of the periodic table are Boron (B), Aluminum (Al), Gallium (Ga), Indium (In), and Thallium (Tl).

2. **Determine the Nature of Each Element**:
- **Boron (B)**:
- Atomic Number: 5
- Classification: Non-metal
- Properties: Boron is not malleable or ductile, and it does not conduct electricity or heat, which are characteristics of non-metals.

- **Aluminum (Al)**:
- Atomic Number: 13
- Classification: Metal
- Properties: Aluminum is a silver-white, soft, non-magnetic, and ductile metal, indicating it is a metal.

- **Gallium (Ga)**:
- Atomic Number: 31
- Classification: Metal
- Properties: Gallium is also a soft, silvery metal, confirming it is a metal.

- **Indium (In)**:
- Atomic Number: 49
- Classification: Metal
- Properties: Indium is soft, ductile, and has a silvery-white color, which are properties of metals.

- **Thallium (Tl)**:
- Atomic Number: 81
- Classification: Metal
- Properties: Thallium is also a metal with similar characteristics.

3. **Conclusion**:
- Among the elements listed, only Boron is classified as a non-metal. Therefore, the answer to the question is Boron.

### Final Answer:
The only non-metal among the group 13 elements is **Boron (B)**.

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