How many ATP are required to fix 10 atoms of nitrogen ?

Options

A. 160 ATPs
B. 140 ATPs
C. 100 ATPs
D. 80 ATPs

Answer

To determine how many ATP are required to fix 10 atoms of nitrogen, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Nitrogen Fixation**: Nitrogen fixation is the process by which atmospheric nitrogen (N₂) is converted into ammonia (NH₃) or other nitrogenous compounds in the soil. This process is primarily carried out by nitrogen-fixing bacteria.

2. **Identify the Reaction**: The general reaction for nitrogen fixation can be summarized as:
\[ N_2 + 8H^+ + 8e^- \rightarrow 2NH_3 + H_2O \]
This reaction indicates that 1 molecule of nitrogen (which contains 2 atoms) is converted into 2 molecules of ammonia.

3. **ATP Requirement for Nitrogen Fixation**: According to the reaction, fixing 1 molecule of nitrogen (2 atoms) requires 16 ATP. Therefore, we can derive the ATP requirement per atom of nitrogen:
- For 2 atoms of nitrogen (1 N₂ molecule), 16 ATP are required.
- For 1 atom of nitrogen, the ATP requirement is:
\[ \frac{16 \text{ ATP}}{2 \text{ atoms}} = 8 \text{ ATP/atom} \]

4. **Calculate ATP for 10 Atoms of Nitrogen**: Now, to find out how many ATP are needed to fix 10 atoms of nitrogen:
\[ 10 \text{ atoms} \times 8 \text{ ATP/atom} = 80 \text{ ATP} \]

5. **Conclusion**: Therefore, the total ATP required to fix 10 atoms of nitrogen is 80 ATP.

### Final Answer:
The answer is **80 ATP**.

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