White phosphorous catches fire in air to produce dense white fumes. This is due to the formation of

Options

A. `P_4 O_(10) `
B. `PH_3`
C. `H_3 PO_3`
D. `H_2 PO_2`

Explanation

**Step-by-Step Solution:**

1. **Identify the Substance**: The question mentions white phosphorus, which is represented by the chemical formula P4.

2. **Understand the Reaction**: When white phosphorus (P4) is exposed to air (which contains oxygen), it reacts with oxygen.

3. **Write the Reaction**: The reaction of white phosphorus with oxygen can be represented as:
\[ P_4 + O_2 \rightarrow P_4O_{10} \]
Here, P4 reacts with oxygen to form phosphorus pentoxide (P4O10).

4. **Balance the Reaction**: To balance the reaction, we need to ensure that the number of atoms of each element is the same on both sides. The balanced equation is:
\[ P_4 + 5O_2 \rightarrow P_4O_{10} \]

5. **Identify the Product**: The product of this reaction, phosphorus pentoxide (P4O10), is known to produce dense white fumes when formed.

6. **Conclusion**: Therefore, the dense white fumes observed when white phosphorus catches fire in air are due to the formation of phosphorus pentoxide (P4O10).

**Final Answer**: The dense white fumes are due to the formation of phosphorus pentoxide (P4O10).

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