Tritium is an isotope of hydrogen whose nucleus triton contains 2 neutrons and 1 proton . Free neutrons decay into `p+bar(e) +bar(n).` If one of the neutrons in Triton decays , it would transform into `He^(3)` nucleus. This does not happen. This is because

Options

A. triton energy is less than that of a `He^(3)` nucleus
B. the electron created in the beta decay proess connot remain in the nucleus
C. Both the neutrons in triton have to decay simultaneously resulting in a nucleus with 3 protons, which is not a `He^(3)` nucleus
D. Ferr neutrons decay due to external perturbations which is absent in triton nucleus

Explanation

To solve the question regarding why Tritium (Triton) does not decay into a Helium-3 nucleus when one of its neutrons decays, we can break down the explanation into clear steps:

### Step-by-Step Solution:

1. **Understanding Tritium**:
Tritium is an isotope of hydrogen represented as \( ^3H \) or \( T \). Its nucleus contains 1 proton and 2 neutrons.

2. **Neutron Decay Process**:
Free neutrons undergo beta decay, transforming into a proton, an electron (beta particle), and an antineutrino. The reaction can be represented as:
\[ n \rightarrow p + e^- + \bar{\nu} \]
If one of the neutrons in Tritium decays, it would convert into a proton.

3. **Result of Neutron Decay in Tritium**:
If one of the neutrons in Tritium decays, the nucleus would then have:
- 2 protons (from the original 1 proton and the newly formed proton)
- 1 neutron (the remaining neutron)

This configuration corresponds to a Helium-3 nucleus (\( ^3He \)).

4. **Binding Energy Consideration**:
The binding energy of a nucleus is a crucial factor in determining its stability. The binding energy of Tritium is less than that of Helium-3. This means that the energy required to keep the nucleus stable in Tritium is lower than that in Helium-3.

5. **Energetic Favorability**:
Since the binding energy of Tritium is less than that of Helium-3, the transformation from Tritium to Helium-3 is not energetically favorable. The decay would require energy that is not available in the Tritium nucleus.

6. **Conclusion**:
Therefore, the reason Tritium does not decay into Helium-3 when one neutron decays is that the binding energy of Tritium is less than that of Helium-3, making the decay energetically unfavorable.

### Final Answer:
Tritium does not decay into Helium-3 because the binding energy of Tritium is less than that of the Helium-3 nucleus.

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