Atomicity of phosphorus is

Options

A. 1. one
B. 2. two
C. 3. three
D. 4. four

Answer

To determine the atomicity of phosphorus, we need to understand what atomicity means and how phosphorus exists in nature.

### Step-by-Step Solution:

1. **Definition of Atomicity**:
Atomicity refers to the number of atoms present in a molecule of a substance.

2. **Phosphorus Forms**:
Phosphorus exists in several allotropes, the most common of which are white phosphorus (P4), red phosphorus, and black phosphorus.

3. **Structure of White Phosphorus**:
- White phosphorus is the most well-known allotrope and consists of tetrahedral P4 molecules.
- In the P4 molecule, each phosphorus atom is bonded to three other phosphorus atoms, forming a tetrahedral shape.

4. **Counting Atoms**:
- In the P4 molecule, there are 4 phosphorus atoms.
- Therefore, the atomicity of white phosphorus is 4.

5. **Conclusion**:
- Since the question asks for the atomicity of phosphorus, and considering the most common form (white phosphorus), we conclude that the atomicity of phosphorus is 4.

### Final Answer:
The atomicity of phosphorus is **4**.

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