Water gas is an important industrial fuel. It is a mixture of

Options

A. `CO+CO_(2)`
B. `H_(2)O`+air
C. `CO+H_(2)`
D. `H_(2)O+CO`

Explanation

**Step-by-Step Solution:**

1. **Understanding Water Gas**: Water gas is recognized as an important industrial fuel. It is essential to identify its components to understand its properties and uses.

2. **Identifying the Components**: Water gas is primarily composed of two gases: carbon monoxide (CO) and hydrogen (H2).

3. **Chemical Reaction for Production**: Water gas is produced by passing steam over red-hot carbon (coke). The chemical reaction can be represented as:
\[ C + H_2O \rightarrow CO + H_2 \]
Here, carbon reacts with water vapor to produce carbon monoxide and hydrogen gas.

4. **Conclusion**: Based on the components identified and the reaction involved, we conclude that water gas is a mixture of carbon monoxide (CO) and hydrogen (H2).

5. **Final Answer**: Therefore, the correct answer to the question is that water gas is a mixture of carbon monoxide (CO) and hydrogen (H2).

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