When a nucleus in an atom undergoes a radioactive decay, the electronic energy levels of the atom:
1. do not change for any type of radioactivity
2. change for \(\alpha\) and \(\beta\text-\)radioactivity but not for \(\gamma\text-\)radioactivity
3. change for \(\alpha\text-\)radioactivity but not for others
4. change for \(\beta\text-\)radioactivity but not for others
Subtopic:  Types of Decay |
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Tritium is an isotope of hydrogen whose nucleus triton contains \(2\) neutrons and \(1\) proton. Free neutrons decay into\(p+e^{-1}+\nu^{-1}.\) If one of the neutrons in Triton decays, it would transform into \(\mathrm{He}^{3}\) nucleus. This does not happen. This is because:
1. triton energy is less than that of a \(\mathrm{He}^{3}\) nucleus.
2. the electron created in the beta decay process cannot remain in the nucleus.
3. both the neutrons in Triton have to decay simultaneously resulting in a nucleus with \(3\) protons, which is not a \(\mathrm{He}^{3}\) nucleus.
4. free neutrons decay due to external perturbations which is absent in Triton nucleus.
Subtopic:  Types of Decay |
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