Name the catalyst [X] for the reaction, `CO(g)+H_(2)(g) overset([x])toHCHO(g)`

Options

A. Ni
B. Cu
C. Cu/ZnO
D. `Cu//Cr_(2)O_(3)`

Explanation

To solve the question regarding the catalyst [X] for the reaction \( CO(g) + H_2(g) \overset{[X]}{\rightarrow} HCHO(g) \), we can follow these steps:

### Step 1: Understand the Reaction
The reaction involves carbon monoxide (CO) and hydrogen gas (H2) reacting to form formaldehyde (HCHO). This type of reaction is typically a hydrogenation process.

### Step 2: Identify the Type of Catalyst Needed
In hydrogenation reactions, a catalyst is often used to facilitate the addition of hydrogen to a compound. Common catalysts for such reactions include metals like nickel (Ni), palladium (Pd), and platinum (Pt).

### Step 3: Consider the Specific Reaction
For the specific reaction of CO and H2 to form HCHO, the catalyst used is usually a metal catalyst that can effectively promote the reaction without being consumed in the process.

### Step 4: Determine the Correct Catalyst
In this case, the catalyst [X] that is commonly used for the conversion of CO and H2 to HCHO is **Rhodium (Rh)** or **Nickel (Ni)**. However, Rhodium is more specifically known for this reaction in industrial processes.

### Final Answer
Thus, the catalyst [X] for the reaction \( CO(g) + H_2(g) \overset{[X]}{\rightarrow} HCHO(g) \) is **Rhodium (Rh)**.

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