Which of the following reactiona is an example of use of water gas in the synthesis of other compounds?

Options

A. `CH_(4(g))+H_(2)O_((g))overset(1270 K)underset(Ni)rarr CO_((g))+H_(2(g))`
B. `CO_((g))+H_(2)O_((g))overset(673 K)underset("Catalyst")rarr CO_(2(g))+H_(2(g))`
C. `C_(n)H_(2n+2)+nH_(2)O_((g))overset(1270 K)underset(Ni)rarr nCO+(2n+1)H_(2)`
D. `CO_((g))+2H_(2(g))overset("Cobalt")underset("Catalyst")rarr CH_(3)OH_((l))`

Explanation

To solve the question regarding the use of water gas in the synthesis of other compounds, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Water Gas**: Water gas is a mixture of carbon monoxide (CO) and hydrogen (H2). It is produced by passing steam over hot carbon (coke) and is often referred to as syngas (synthesis gas).

2. **Identify the Reaction**: The question asks for a reaction that uses water gas in the synthesis of other compounds. A well-known reaction that utilizes water gas is the synthesis of methanol (CH3OH) from carbon monoxide and hydrogen.

3. **Write the Reaction**: The chemical reaction for the synthesis of methanol from water gas can be represented as:
\[ CO + 2H_2 \rightarrow CH_3OH \]
Here, carbon monoxide reacts with hydrogen gas to produce methanol.

4. **Catalyst Used**: In this reaction, cobalt (Co) is often used as a catalyst to facilitate the reaction process.

5. **Balance the Reaction**: The reaction is already balanced with respect to the number of atoms of each element on both sides.

6. **Conclusion**: Based on the understanding of water gas and the reaction identified, the correct answer to the question is that the reaction involving the synthesis of methanol from carbon monoxide and hydrogen gas is an example of the use of water gas in the synthesis of other compounds.

### Final Answer:
The reaction \( CO + 2H_2 \rightarrow CH_3OH \) is an example of the use of water gas in the synthesis of methanol.

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