Which of the following nuclear reaction occurs in nature for the formation of tritium?

Options

A. `._(3)Li^(6) + ._(0)n^(1) rarr ._(2)He^(4) + ._(1)H^(3)`
B. `._(5)B^(10) + ._(0)n^(1) rarr 2 ._(2)He^(4) + ._(1)H^(3)`
C. `._(7)N^(14) + ._(0)n^(1) rarr ._(6)C^(12) + ._(1)H^(3)`
D. `._(4)Be^(9) + ._(1)D^(2) rarr 2 ._(2)He^(4) + ._(1)H^(3)`

Answer

To determine which nuclear reaction occurs naturally for the formation of tritium (³H or ¹H₃), we can analyze the process step by step.

### Step-by-Step Solution:

1. **Identify Tritium**: Tritium is a hydrogen isotope with one proton and two neutrons, represented as ³H or ¹H₃.

2. **Consider Natural Reactions**: We need to identify which nuclear reactions can lead to the formation of tritium in nature.

3. **Look at Nitrogen Isotope**: One of the known natural reactions involves nitrogen-14 (¹⁴N), which is a stable isotope of nitrogen with 7 protons and 7 neutrons.

4. **Neutron Bombardment**: In nature, nitrogen-14 can undergo a nuclear reaction when it captures a slow-moving neutron (n). This is crucial because the neutron must be slow-moving for the reaction to occur naturally.

5. **Reaction Equation**: The reaction can be represented as:
\[ ^{14}_{7}N + ^{1}_{0}n \rightarrow ^{12}_{6}C + ^{3}_{1}H \]
In this reaction, nitrogen-14 absorbs a neutron and transforms into carbon-12 (¹²C), while also producing tritium (³H).

6. **Conclusion**: Therefore, the natural nuclear reaction that leads to the formation of tritium is the bombardment of nitrogen-14 with a slow-moving neutron, resulting in the production of carbon-12 and tritium.

### Final Answer:
The correct answer is that the nuclear reaction involving nitrogen-14 (¹⁴N) and a slow-moving neutron (n) occurs in nature for the formation of tritium (³H).

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