Conversion of `NH_3 to NO_2^(-) to NO_3^(-) ` is called

Options

A. Ammonification
B. Nitrification
C. Denitification
D. Biological `N_2 ` - fixation

Answer

**Step-by-Step Solution:**

1. **Understanding the Compounds:**
- The question involves the conversion of ammonia (NH₃) to nitrite (NO₂⁻) and then to nitrate (NO₃⁻).

2. **Identifying the Process:**
- This conversion process is a part of the nitrogen cycle, specifically involving the transformation of nitrogen compounds in the soil.

3. **Recognizing the Key Term:**
- The process that converts ammonia (NH₃) to nitrite (NO₂⁻) and then to nitrate (NO₃⁻) is known as **nitrification**.

4. **Role of Bacteria:**
- Nitrification is carried out by specific types of bacteria.
- The first step involves bacteria such as **Nitrosomonas**, which convert ammonia (NH₃) to nitrite (NO₂⁻).
- The second step involves bacteria such as **Nitrobacter**, which convert nitrite (NO₂⁻) to nitrate (NO₃⁻).

5. **Conclusion:**
- Therefore, the conversion of NH₃ to NO₂⁻ to NO₃⁻ is called **nitrification**.

**Final Answer:**
The conversion of NH₃ to NO₂⁻ to NO₃⁻ is called **nitrification**.

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