Radioactivity is generally not found in

Options

A. Light nuclei
B. Stable nuclei
C. Heavy nuclei
D. Nuclei of intermediate mass

Answer

To solve the question "Radioactivity is generally not found in," we need to analyze the options given and understand the concept of radioactivity.

### Step-by-Step Solution:

1. **Understanding Radioactivity**:
- Radioactivity is a process by which unstable atomic nuclei lose energy by emitting radiation. This can occur in the form of alpha particles, beta particles, or gamma rays. The goal of this process is to achieve a more stable configuration.

2. **Identifying Types of Nuclei**:
- **Light Nuclei**: Generally, these are stable and do not exhibit radioactivity. Examples include elements like helium and lithium.
- **Stable Nuclei**: These nuclei do not undergo radioactive decay as they are already in a stable state.
- **Intermediate Mass Nuclei**: These can sometimes exhibit radioactivity, but many are stable as well.
- **Heavy Nuclei**: These are typically unstable and prone to radioactivity. Examples include uranium, thorium, and radium.

3. **Analyzing the Options**:
- Based on the understanding of the types of nuclei, we can deduce that light nuclei and stable nuclei are less likely to exhibit radioactivity compared to heavy nuclei.

4. **Conclusion**:
- Therefore, the correct answer to the question "Radioactivity is generally not found in" would be **light nuclei** or **stable nuclei**.

### Final Answer:
Radioactivity is generally not found in **light nuclei** or **stable nuclei**.

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