Water gas consists of

Options

A. water vapour and coal dust
B. a mixture of carbon monoxide and hydrogen
C. a mixture of carbon monoxide and nitrogen
D. water vapour and methane

Explanation

**Step-by-Step Solution:**

1. **Understanding Water Gas**: Water gas is a mixture of carbon monoxide (CO) and hydrogen gas (H2). It is an important industrial gas used in various chemical processes.

2. **Formation of Water Gas**: Water gas is produced when steam (water vapor) is passed over red-hot coke (a form of carbon). The high temperature allows a reaction to occur.

3. **Chemical Reaction**: The reaction that takes place can be represented by the following equation:
\[ C (s) + H_2O (g) \rightarrow CO (g) + H_2 (g) \]
Here, solid carbon (from coke) reacts with steam to produce carbon monoxide and hydrogen gas.

4. **Conditions for Reaction**: The coke must be red hot (around 1000°C) for the reaction to proceed efficiently. The high temperature provides the necessary energy to break the bonds in water molecules and facilitate the reaction.

5. **Conclusion**: Therefore, water gas consists of carbon monoxide (CO) and hydrogen (H2), formed by the reaction of steam with red-hot coke.

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