One of the commercial production methods of methanol is :

Options

A. By reaction of methane and water steam at `900^(@)` in presence of Ni catalyst
B. Induced reduction of carbon monoxide in presence of `ZnO + Cr_(2) O_(3)`
C. By reducing formaldehyde with `LiAIH_(4)`
D. None of these

Answer

To determine one of the commercial production methods of methanol, we will analyze the provided statements step by step.

### Step 1: Analyze the First Statement
The first statement mentions the reaction of methane and steam at 900 °C in the presence of nickel as a catalyst.

- **Reaction**: CH₄ (methane) + H₂O (steam) → CO (carbon monoxide) + H₂ (hydrogen gas)

This reaction produces synthesis gas (syngas), which is a mixture of carbon monoxide and hydrogen. While this is a step in the process of producing methanol, it does not directly produce methanol itself. Therefore, this method is not a commercial production method for methanol.

**Hint**: Check if the reaction directly produces methanol or just precursor substances.

### Step 2: Analyze the Second Statement
The second statement describes the reduction of carbon monoxide in the presence of zinc oxide and chromium oxide.

- **Reaction**: CO + 2H₂ → CH₃OH (methanol)

In this method, carbon monoxide reacts with hydrogen gas under high temperature and pressure (450-500 °C) using zinc oxide and chromium oxide as catalysts to produce methanol. This is indeed a recognized industrial and commercial method for producing methanol.

**Hint**: Look for reactions that lead directly to the formation of methanol.

### Step 3: Analyze the Third Statement
The third statement involves reducing formaldehyde with lithium aluminum iodide.

- **Reaction**: HCHO (formaldehyde) + LiAlI₄ → CH₃OH (methanol) + HCOOH (formic acid)

While this reaction can produce methanol, it is not a commercial method. Formaldehyde is prone to oxidation when exposed to air, which complicates its use in large-scale methanol production. Thus, this method is not considered commercial.

**Hint**: Consider the stability and practicality of the reactants in a commercial setting.

### Step 4: Conclusion
Based on the analysis of the statements:
- The first statement does not produce methanol directly.
- The second statement describes a valid commercial production method for methanol.
- The third statement, while it produces methanol, is not practical for commercial use.

Thus, the correct answer is the second statement: **"By the reduction of carbon monoxide in the presence of zinc oxide and chromium oxide at high temperature and pressure."**

**Final Answer**: The commercial production method of methanol is by the reduction of carbon monoxide in the presence of zinc oxide and chromium oxide at high temperature and pressure.