Traces of molybdenum are used with finely divided iron which acts as a catalyst during Haber's process for synthesis of ammonia . The Mo

Options

A. acts as a promoter to increase the activity of the catalyst
B. acts as a poison to decrease the activity of the catalyst
C. provides a new pathway to the reaction
D. forms another intermediate compound with lesser activation energy .

Explanation

To solve the question regarding the role of molybdenum in the Haber process for ammonia synthesis, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understand the Haber Process**: The Haber process is a chemical reaction that synthesizes ammonia (NH₃) from nitrogen (N₂) and hydrogen (H₂) gases. The balanced equation for this reaction is:
\[ N_2(g) + 3H_2(g) \rightarrow 2NH_3(g) \]

2. **Identify the Catalyst**: In this process, finely divided iron (Fe) is used as a catalyst. A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process.

3. **Role of Molybdenum**: Molybdenum (Mo) is mentioned to be used in traces along with iron. In this context, molybdenum acts as a promoter. A promoter is a substance that enhances the activity of a catalyst.

4. **Differentiate Between Catalyst, Promoter, and Poison**:
- **Catalyst**: Increases the reaction rate and is not consumed.
- **Promoter**: Enhances the effectiveness of a catalyst.
- **Poison**: Decreases the activity of a catalyst.

5. **Conclusion**: Since molybdenum is used to enhance the activity of iron in the Haber process, the correct answer to the question is that molybdenum acts as a promoter.

### Final Answer:
Molybdenum acts as a promoter to increase the activity of the catalyst (iron) in the Haber process.