Which one of the following elements has the highest melting point?

Options

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

Answer

To determine which element has the highest melting point among the boron family elements, we can follow these steps:

### Step 1: Identify the Elements in the Boron Family
The boron family consists of the following elements:
- Boron (B)
- Aluminum (Al)
- Gallium (Ga)
- Indium (In)
- Thallium (Tl)

### Step 2: Research the Melting Points of Each Element
Next, we need to find the melting points of these elements:
- Boron (B): 2352 K
- Aluminum (Al): 933 K
- Gallium (Ga): 302.9 K
- Indium (In): 1566 K
- Thallium (Tl): 577 K

### Step 3: Compare the Melting Points
Now, we compare the melting points of all the elements listed above:
- Boron: 2352 K
- Aluminum: 933 K
- Gallium: 302.9 K
- Indium: 1566 K
- Thallium: 577 K

### Step 4: Identify the Element with the Highest Melting Point
From the comparison, it is clear that Boron has the highest melting point at 2352 K.

### Step 5: Explain the Reason for Boron's High Melting Point
Boron has a high melting point due to:
- Its small atomic size, which allows it to form strong covalent bonds.
- The closed-packed structure of boron, which contributes to its stability and high melting point.

### Conclusion
Thus, the element with the highest melting point in the boron family is **Boron (B)** with a melting point of **2352 K**.

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