________is a fuel composed mainly of nitrogen `(N_(2))` and carbon monoxide (CO), formed by passing air through red hot coke.

Options

A. water gas
B. producer gas
C. Coal tar
D. Paraffin.

Answer

To answer the question, we need to identify the fuel that is composed mainly of nitrogen (N₂) and carbon monoxide (CO), which is formed by passing air through red hot coke. Let's break it down step by step.

### Step-by-Step Solution:

1. **Understanding the Components**:
- The question mentions two main components: nitrogen (N₂) and carbon monoxide (CO).
- Nitrogen is a major component of air, while carbon monoxide is a byproduct of incomplete combustion of carbon-containing materials.

2. **Formation Process**:
- The process described involves passing air through red hot coke.
- Coke is a solid carbonaceous material derived from coal, and when it is heated in the presence of air, it reacts to produce gases.

3. **Identifying the Gas Mixture**:
- The mixture of nitrogen and carbon monoxide produced in this process is known as a specific type of gas.
- This gas is characterized by its composition and the method of its formation.

4. **Naming the Gas**:
- The gas produced from this reaction is commonly referred to as "producer gas."
- Producer gas is a mixture primarily consisting of carbon monoxide (CO) and nitrogen (N₂), along with small amounts of other gases.

5. **Conclusion**:
- Therefore, the answer to the question is "producer gas."

### Final Answer:
**Producer gas** is a fuel composed mainly of nitrogen (N₂) and carbon monoxide (CO), formed by passing air through red hot coke.

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