The instability of a nucleus is due to

Options

A. High proton electron ratio
B. High electron neutron ratio
C. Low proton electron ratio
D. Low proton neutron ratio

Explanation

**Step-by-Step Solution:**

1. **Understanding Nucleus Composition**: The nucleus of an atom is made up of protons and neutrons, which are collectively referred to as nucleons. The stability of the nucleus is influenced by the ratio of protons to neutrons.

2. **Proton to Neutron Ratio**:
- A low proton to neutron ratio indicates that there are fewer protons compared to neutrons in the nucleus.
- A high proton to neutron ratio indicates that there are more protons compared to neutrons.

3. **Instability Factors**:
- If the neutron to proton ratio is less than 1 (meaning there are more protons than neutrons), the nucleus tends to be unstable and may undergo alpha emission.
- If the neutron to proton ratio is greater than 1 (meaning there are more neutrons than protons), the nucleus can also be unstable and may undergo beta emission.

4. **Conclusion**: The instability of a nucleus can be attributed to either a low or high proton to neutron ratio. Therefore, both conditions can lead to instability, but the question specifically asks for one of them.

5. **Final Answer**: The instability of a nucleus is due to a low proton to neutron ratio or a high proton to neutron ratio.

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