The nature of bonding in crystalline boron is

Options

A. Covalent
B. Ionic
C. Metallic
D. Coordinate .

Answer

To determine the nature of bonding in crystalline boron, we will analyze its electronic configuration, position in the periodic table, and the types of bonds it can form.

### Step-by-Step Solution:

1. **Identify the Position of Boron in the Periodic Table:**
- Boron is located in Group 13 of the periodic table and is classified as a non-metal.

2. **Determine the Electronic Configuration:**
- The atomic number of boron is 5, and its electronic configuration is \(1s^2 2s^2 2p^1\). This means it has 3 valence electrons (2 in the s orbital and 1 in the p orbital).

3. **Analyze the Types of Bonds:**
- Since boron is a non-metal, it cannot form metallic bonds. Therefore, options involving metallic bonding are incorrect.
- Boron cannot form ionic bonds because it does not have a complete octet and cannot easily gain or lose electrons to form charged ions.
- Boron has one vacant p orbital, which means it cannot donate both electrons to form a coordinate bond with another atom, as it does not have a complete octet.

4. **Covalent Bonding:**
- Given that boron can share its electrons with other atoms, it can form covalent bonds. Boron can bond with other boron atoms or other non-metals by sharing electrons, similar to how carbon behaves.
- The small size of boron allows it to form strong covalent bonds, creating a network structure in crystalline boron.

5. **Conclusion:**
- Therefore, the nature of bonding in crystalline boron is primarily covalent bonding.

### Final Answer:
The nature of bonding in crystalline boron is covalent bonding.

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