The middle zone of a candle flame is also called the zone of _____ combustion.

Options

A. Full
B. Incomplete
C. Complete
D. Partial

Answer

To answer the question, "The middle zone of a candle flame is also called the zone of _____ combustion," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Candle Flame Structure**: A candle flame consists of three zones: the outer zone, the middle zone, and the inner zone. Each zone has different characteristics based on the availability of oxygen and the type of combustion occurring.

2. **Identifying the Middle Zone**: The middle zone of the candle flame is where the combustion process occurs with limited oxygen supply. This limited oxygen leads to incomplete combustion.

3. **Types of Combustion**: There are generally two types of combustion:
- **Complete Combustion**: This occurs when there is a sufficient supply of oxygen, resulting in the complete oxidation of the fuel, producing carbon dioxide and water.
- **Incomplete Combustion**: This occurs when the oxygen supply is limited, leading to the production of carbon monoxide, soot, or other products along with carbon dioxide and water.

4. **Analyzing the Options**:
- The question provides options that include complete combustion, incomplete combustion, and partial combustion.
- Since the middle zone has limited oxygen supply, it cannot support complete combustion.

5. **Conclusion**: Therefore, the middle zone of a candle flame is called the zone of **incomplete combustion**. It can also be referred to as the zone of **partial combustion**, as both terms imply that the combustion is not complete due to insufficient oxygen.

### Final Answer:
The middle zone of a candle flame is also called the zone of **incomplete combustion** (or **partial combustion**).

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