The central zone of the candle flame is luminous due to

Options

A. incomplete combustion of wax vapours
B. complete combustion of wax vapours
C. no combustion of wax vapours
D. formation of carbon dioxide.

Explanation

To answer the question "The central zone of the candle flame is luminous due to," we can break down the explanation into clear steps:

### Step-by-Step Solution:

1. **Understanding the Candle Flame Structure**:
- A candle flame consists of different zones, including the outer zone, inner zone, and central zone. Each zone has different characteristics based on the combustion process occurring there.

2. **Identifying the Central Zone**:
- The central zone of the candle flame is known as the luminous zone. This is the area that emits light and is visible to the naked eye.

3. **Reason for Luminance**:
- The central zone is luminous primarily due to **incomplete combustion** of wax vapor. This occurs when there is not enough oxygen available for complete combustion.

4. **Combustion Process**:
- In the central zone, the wax vapor (which is primarily made up of hydrocarbons) does not burn completely because of the limited supply of oxygen. This incomplete combustion leads to the formation of soot particles.

5. **Formation of Soot**:
- The soot particles are small carbon particles that glow when heated, which is why the central zone appears luminous.

6. **Conclusion**:
- Therefore, the central zone of the candle flame is luminous due to the incomplete combustion of wax vapor, resulting in the formation of glowing soot particles.

### Final Answer:
The central zone of the candle flame is luminous due to the incomplete combustion of wax vapor.

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