Answer the following :
Mixture of CO and `H_2` is used for preparation ......... .

Answer

To answer the question regarding the mixture of carbon monoxide (CO) and hydrogen (H2), we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Mixture**: The mixture of carbon monoxide (CO) and hydrogen (H2) is commonly referred to as "water gas" or "synthesis gas" (syngas).

2. **Chemical Reaction**: This mixture is primarily used in the production of methanol (CH3OH). The reaction can be represented as:
\[ CO + 2H_2 \rightarrow CH_3OH \]

3. **Conditions for Reaction**: The production of methanol from this mixture typically occurs under specific conditions:
- **Pressure**: Approximately 300 atm
- **Temperature**: About 300 degrees Celsius

4. **Catalysts Used**: The catalysts that facilitate this reaction include a combination of zinc oxide (ZnO) and chromium oxide (CrO3). These catalysts help in increasing the efficiency of the reaction.

5. **Conclusion**: Therefore, the mixture of CO and H2 is primarily used for the preparation of methanol.

### Final Answer:
The mixture of CO and H2 is used for the preparation of methanol (CH3OH).

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