During synthesis of ammonia by Haber's process,
'CO' acts is

Options

A. Poison
B. Promoter
C. Catalyst
D. Inert substance

Answer

**Step-by-Step Solution:**

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

2. **Role of Catalyst:**
In the Haber process, iron (Fe) and molybdenum (Mo) are used as catalysts. Catalysts are substances that increase the rate of a chemical reaction without being consumed in the process.

3. **Effect of CO:**
Carbon monoxide (CO) can also act as a catalyst. However, in the context of the Haber process, CO is detrimental because it decreases the activity of the iron catalyst. This means that the presence of CO reduces the efficiency of ammonia production.

4. **Classification of CO:**
Since CO inhibits the reaction and reduces the effectiveness of the catalyst, it is classified as a "poison" for the catalyst. A catalyst poison is a substance that decreases the activity of a catalyst.

5. **Conclusion:**
Therefore, during the synthesis of ammonia by the Haber process, CO acts as a poison.

**Final Answer:**
CO acts as a poison during the synthesis of ammonia by the Haber process.

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