Nitrogen and hydrogen combine to form ammonia under high temperature and pressure conditions. This is an example of

Options

A. (a) biological `N_(2)` fixation
B. (b) natural `N_(2)` fixation
C. (c) industrial `N_(2)` fixation
D. (d) electrical `N_(2)` fixation

Explanation

**Step-by-Step Solution:**

1. **Identify the Reactants and Products**: The question states that nitrogen (N₂) and hydrogen (H₂) combine to form ammonia (NH₃).

2. **Understand the Conditions**: The process occurs under high temperature and high pressure conditions. This is a crucial detail as it helps to differentiate between types of nitrogen fixation.

3. **Recall Types of Nitrogen Fixation**: There are different types of nitrogen fixation:
- Biological nitrogen fixation (occurs in living organisms, often involving bacteria)
- Natural nitrogen fixation (occurs through natural processes like lightning)
- Industrial nitrogen fixation (occurs in industrial settings, typically involving the Haber process)
- Electrical nitrogen fixation (not a commonly recognized category)

4. **Match the Process with the Correct Type**: Given that the process involves high temperature and pressure to combine nitrogen and hydrogen to produce ammonia, it aligns with the industrial nitrogen fixation process, specifically the Haber process.

5. **Conclude the Answer**: Therefore, the correct answer to the question is that the combination of nitrogen and hydrogen to form ammonia under high temperature and pressure conditions is an example of **industrial nitrogen fixation**.

**Final Statement**: Hence, nitrogen and hydrogen combine to form ammonia under high temperature and pressure conditions in industrial nitrogen fixation. The correct answer is option C: industrial nitrogen fixation.

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