The catalyst used in the manufacture of ammonia by Haber process is

Options

A. Pt
B. Fe
C. Mo
D. `V_2 O_5`

Answer

To solve the question regarding the catalyst used in the manufacture of ammonia by the Haber process, we can follow these steps:

### Step 1: Understand the Haber Process
The Haber process is a method of synthesizing ammonia (NH3) from nitrogen (N2) and hydrogen (H2) gases. This reaction occurs under high temperature and high pressure conditions.

**Hint:** Remember that the Haber process involves the combination of nitrogen and hydrogen gases.

### Step 2: Identify the Reaction Conditions
The reaction typically takes place at temperatures ranging from 400 to 450 degrees Celsius and at pressures around 200 atmospheres.

**Hint:** High temperature and pressure are crucial for the efficiency of the Haber process.

### Step 3: Determine the Catalyst Used
In the Haber process, a catalyst is required to increase the rate of the reaction. The catalyst used is iron (Fe). Additionally, a promoter, which enhances the activity of the catalyst, is often used, and in this case, molybdenum (Mo) serves as the promoter.

**Hint:** Focus on the role of the catalyst and promoter in chemical reactions.

### Step 4: Write the Balanced Equation
The balanced chemical equation for the Haber process can be represented as:
\[ N_2 + 3H_2 \rightarrow 2NH_3 \]
This indicates that one molecule of nitrogen reacts with three molecules of hydrogen to produce two molecules of ammonia.

**Hint:** Balancing the equation helps in understanding the stoichiometry of the reaction.

### Step 5: Identify the Correct Option
From the information gathered, we can conclude that the catalyst used in the manufacture of ammonia by the Haber process is iron (Fe). If the options provided include iron, that would be the correct answer.

**Hint:** Look for the option that mentions iron as the catalyst.

### Final Answer
The catalyst used in the manufacture of ammonia by the Haber process is **iron (Fe)**.