Dihydration can be prepared on a commercial scale by the action of steam on hydrocarbons, when a mixture of CO and `H_(2)` gas is formed. It is known as

Options

A. water gas
B. producer gas
C. industrial gas
D. fuel gas

Explanation

**Step-by-Step Solution:**

1. **Understanding Dihydrogen Production**: Dihydrogen (H₂) can be produced on a commercial scale through the process of steam reforming, which involves the reaction of steam with hydrocarbons.

2. **Reaction Overview**: When hydrocarbons (like methane, CH₄) react with steam, they produce carbon monoxide (CO) and dihydrogen (H₂). The general reaction can be represented as:
\[ \text{Hydrocarbon} + \text{H}_2\text{O} \rightarrow \text{CO} + \text{H}_2 \]

3. **Identifying the Gas Mixture**: The mixture of carbon monoxide (CO) and dihydrogen (H₂) produced from this reaction is known as "water gas".

4. **Clarifying Water Gas**: Initially, water gas was defined as a mixture of CO and H₂ in a 1:1 ratio. However, it is now understood that water gas can be any proportion of CO and H₂.

5. **Distinguishing from Producer Gas**: It is important to differentiate water gas from producer gas. Producer gas is characterized by a different ratio of CO to H₂, specifically a 1:3 ratio.

6. **Conclusion**: Therefore, the mixture of CO and H₂ produced by the action of steam on hydrocarbons is referred to as "water gas" or "synthesis gas" (syngas).

**Final Answer**: The mixture of CO and H₂ gas formed by the action of steam on hydrocarbons is known as **water gas** or **syngas**.

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