The process by which ammonia is formed from nitrogen and hydrogen is

Options

A. Contact process
B. Haber process
C. Ostwald process
D. Hydrogenation process

Answer

To solve the question regarding the process by which ammonia is formed from nitrogen and hydrogen, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reaction**: The formation of ammonia (NH₃) from nitrogen (N₂) and hydrogen (H₂) can be represented by the chemical equation:
\[ N_2 + 3H_2 \rightarrow 2NH_3 \]

2. **Determine the Process**: The process that facilitates this reaction is known as the Haber process. This process synthesizes ammonia from its elemental gases under specific conditions.

3. **Conditions of the Haber Process**:
- **Temperature**: The reaction typically occurs at a temperature of about 673 Kelvin.
- **Pressure**: The reaction is conducted at high pressures, around 200 atmospheres.
- **Catalyst**: Iron is commonly used as a catalyst to speed up the reaction, and molybdenum can be used as a promoter to enhance the effectiveness of the catalyst.

4. **Evaluate the Options**:
- **Contact Process**: This is used for the production of sulfuric acid (H₂SO₄), not ammonia.
- **Haber Process**: This is the correct process for the formation of ammonia.
- **Ostwald Process**: This is used for the production of nitric acid (HNO₃), not ammonia.
- **Hydrogenation Process**: This involves the addition of hydrogen to unsaturated compounds to form saturated compounds, which is not relevant to ammonia synthesis.

5. **Conclusion**: Based on the evaluation of the options, the correct answer is the Haber process.

### Final Answer:
The process by which ammonia is formed from nitrogen and hydrogen is known as the **Haber process**.

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