When a mixture of air and steam is passed over red hot coke, the outgoing gas is:

Options

A. Producer gas
B. Water gas
C. Coal gas
D. None of these

Answer

To solve the question, we need to analyze the reaction that occurs when a mixture of air and steam is passed over red hot coke. Here are the steps to derive the answer:

### Step 1: Understand the Components
- **Coke** is primarily carbon (C) and is used as a reducing agent in various chemical reactions.
- **Air** contains oxygen (O2) and nitrogen (N2).
- **Steam** is water in the form of vapor (H2O).

### Step 2: Identify the Reaction
When red hot coke reacts with air (specifically the oxygen in the air) and steam, two main reactions can occur:
1. The reaction of carbon with oxygen from air to produce carbon monoxide (CO).
2. The reaction of carbon with steam to produce carbon monoxide (CO) and hydrogen gas (H2).

### Step 3: Write the Chemical Equations
1. **C + O2 → 2CO** (Carbon reacts with oxygen to form carbon monoxide)
2. **C + H2O → CO + H2** (Carbon reacts with steam to form carbon monoxide and hydrogen)

### Step 4: Analyze the Products
- The products of these reactions include carbon monoxide (CO) and potentially hydrogen (H2) if steam is present.
- However, when air is mixed with steam and passed over red hot coke, the predominant product is carbon monoxide due to the high temperature and the presence of oxygen.

### Step 5: Identify the Outgoing Gas
The outgoing gas from the reaction will primarily be carbon monoxide (CO) along with nitrogen (N2) from the air. This mixture is known as **producer gas**.

### Conclusion
The correct answer to the question is that the outgoing gas is **producer gas**, which mainly consists of carbon monoxide and nitrogen.

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