Which of the region of a flame is called luminous zone?

Options

A. Outermost Zone
B. Inner Zone
C. Middle Zone
D. Uppermost area of Furnace

Explanation

To determine which region of a flame is called the luminous zone, we can analyze the structure of a flame, typically seen in a candle flame.

### Step-by-Step Solution:

1. **Understand the Structure of a Flame**: A flame consists of three main zones: the outer zone, the middle zone, and the inner zone. Each of these zones has different characteristics.

2. **Identify the Zones**:
- **Outer Zone**: This is the area surrounding the flame, which is usually blue and is where complete combustion occurs.
- **Middle Zone**: This is the area where the flame appears bright and yellow. It is the region where incomplete combustion takes place, and it is known for producing light.
- **Inner Zone**: This is the area closest to the wick, which is dark and not very luminous. It indicates a lack of combustion.

3. **Define the Luminous Zone**: The luminous zone is characterized by its brightness and is primarily located in the middle part of the flame. This is where the flame emits light due to the presence of incandescent particles.

4. **Conclusion**: Therefore, the region of the flame that is called the luminous zone is the **Middle Zone**.

### Final Answer:
The luminous zone of a flame is the **Middle Zone**.

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