Which of the following is a non meta!?

Options

A. Gallium
B. Indium
C. Boron
D. Aluminium

Explanation

To determine which of the following elements is a non-metal among gallium, aluminium, boron, and thallium, we can follow these steps:

### Step 1: Identify the Elements
The elements given in the question are:
- Gallium (Ga)
- Aluminium (Al)
- Boron (B)
- Thallium (Tl)

### Step 2: Locate the Elements in the Periodic Table
These elements belong to Group 13 of the periodic table. The group consists of:
- Boron (B) - the first element in the group
- Aluminium (Al) - the second element
- Gallium (Ga) - the third element
- Indium (In) - the fourth element
- Thallium (Tl) - the fifth element

### Step 3: Determine the Metallic Character
In general, as we move down a group in the periodic table, the metallic character of the elements increases. This means that:
- Boron, being at the top of the group, has the least metallic character and is classified as a non-metal.
- Aluminium and Gallium are metals.
- Thallium, being further down, is also a metal.

### Step 4: Conclusion
Among the given options, Boron is the only non-metal.

### Final Answer
The non-metal among the given elements is **Boron (B)**.

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