Yellow phosphorus in the molecular state exists as :

Options

A. `P_4`
B. `P_5`
C. `P_9`
D. `P_(10)`

Answer

To determine the molecular state of yellow phosphorus, we need to analyze the forms of phosphorus and identify the correct molecular formula.

### Step-by-Step Solution:

1. **Identify the Forms of Phosphorus:**
Phosphorus exists in several allotropes, including white phosphorus, yellow phosphorus, and red phosphorus. Each allotrope has a different molecular structure.

2. **Understand Yellow Phosphorus:**
Yellow phosphorus is one of the allotropes of phosphorus. It is important to note that yellow phosphorus is often considered a less stable form compared to white phosphorus.

3. **Molecular Structure of Yellow Phosphorus:**
Yellow phosphorus primarily exists in the molecular form of \( P_4 \). This means that in its molecular state, yellow phosphorus consists of four phosphorus atoms bonded together.

4. **Visualize the Structure of \( P_4 \):**
The \( P_4 \) molecule has a tetrahedral structure where each phosphorus atom is bonded to three other phosphorus atoms. This arrangement is crucial for understanding the stability and reactivity of yellow phosphorus.

5. **Conclusion:**
Based on the above analysis, we conclude that yellow phosphorus in its molecular state exists as \( P_4 \).

### Final Answer:
Yellow phosphorus in the molecular state exists as \( P_4 \).

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